Articles in press have been peer-reviewed and accepted, which are not yet assigned to volumes /issues, but are citable by Digital Object Identifier (DOI).
Research progress on aromatization of C6 + n-alkanes
ZHOU Qiu-ming, WANG Sen, QIN Zhang-feng, DONG Mei, WANG Jian-guo, FAN Wei-bin
 doi: 10.1016/S1872-5813(23)60357-3
Abstract(100) HTML(33) PDF 10650KB(63)
Conversion of saturated straight-chain alkanes generated in the deep desulfurization process of fluid catalytic cracking (FCC) gasoline and the coal-to-oil processes into aromatics via alkane aromatization is an important non-petroleum route for the preparation of aromatics that effectively improves the quality of oil. The aromatization technology of C2−C5 light hydrocarbons is relatively mature and has been used in industry. However, for the aromatization of ${\rm{C}}_6^+ $ n-alkanes, the aromatics yield is still very low due to the complex reaction process and the competition of various elemental reactions. In addition, the catalysts usually suffer from rapid deactivation. In this work, we summarize the recent advances in the aromatization of ${\rm{C}}_6^+ $ n-alkanes. The reaction mechanism of aromatization of ${\rm{C}}_6^+ $ alkanes and the effects of the dispersion of metal sites, electronic state, and acidity, morphology and pore structure of the support on the catalytic performance are discussed in detail.
Effect of framework structure of ZSM-11 and ZSM-5 zeolites on their catalytic performance in the conversion of methanol to olefins
YUAN Kai, JIA Xiang-yu, WANG Sen, FAN Sheng, HE Shi-pei, WANG Peng-fei, DONG Mei, QIN Zhang-feng, FAN Wei-bin, WANG Jian-guo
 doi: 10.1016/S1872-5813(23)60361-5
Abstract(113) HTML(49) PDF 2907KB(22)
The catalytic performance of zeolites are closely related to their framework structure and a clear understanding of such a structure-performance relationship is of great significance in revealing catalytic reaction mechanism as well as in exploring efficient zeolite catalysts. Herein, ZSM-11 and ZSM-5 zeolites with similar morphology, crystal size, textural properties and acidity were hydrothermally synthesized; the effect of their difference in the 10-ring channels on the catalytic performance in the conversion of methanol to olefins (MTO) were investigated by using various characterization techniques. The results indicate that in comparison with the straight channel of ZSM-11, the sinusoidal channel of ZSM-5 has greater diffusion resistance, which promotes the hydrogen-transfer in higher olefins, conduces to forming more polymethylbenzene species and then raises the contribution of aromatic-based cycle. In contrast, ZSM-11 with straight channel can abate the formation of polymethylbenzene species and enhance the alkene-based cycle. As a result, compared with ZSM-5-60 of similar morphology and acidity, ZSM-11-60 as a catalyst in MTO exhibits longer lifetime (98.3 h vs. 65.4 h) and higher selectivity to propene (34.6% vs. 27.4%). The insight shown in this work helps to have a better understanding of the relation between zeolite structure and catalytic performance in MTO and is then beneficial to the development of better catalysts and processes for MTO.
A research paper
CO2-assisted oxidative dehydrogenation of ethane to ethylene over the ZnO-ZrO2 catalyst
LIAO Duo-hua, YANG Liang, SONG Geng-zhe, MA Xue-dong, LI Shuang
 doi: 10.1016/S1872-5813(23)60360-3
Abstract(56) HTML(26) PDF 19608KB(11)
The ZnO-ZrO2 catalyst was prepared by the deposition-precipitation method using ZrO2 as the carrier obtained from calcining commercial zirconium hydroxide (Zr(OH)4). And the catalytic performance was evaluated at 873 K in CO2-assisted ethane oxidative dehydrogenation reaction (CO2-ODHE). The physical-chemical properties and morphology were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), Raman spectra, High-resolution transmission electron microscopy (HRTEM), X-ray photoelectron spectra (XPS), CO2 temperature-programmed desorption (CO2-TPD). The results show that ZnO were doped into the surface lattice of ZrO2 on the 5%ZnO-ZrO2 catalyst, generating highly dispersed ZnO species and oxygen-deficient regions on catalyst surface. 5%ZnO-ZrO2 catalyst could selectively breaking C−H bond instead of C−C bond, delivering excellent catalytic performance. 210 μmol/(gcat·min) of C2H4 formation rate could compare favorably with the data reported on noble metal and transition metal carbides. Additionally, the possible mechanism is discussed.
A research paper
Wet removal of elemental mercury by acid-assisted electrochemical oxidation method
ZHANG Qian-qian, ZHANG An-chao, MENG Fan-mao, LIU Yan-wen, SUN Zhi-jun, LI Hai-xia, ZHENG Hai-kun
 doi: 10.1016/S1872-5813(23)60371-8
Abstract(18) HTML(15) PDF 4611KB(1)
As a global pollutant, mercury emission is increasingly restricted in recent years. It is urgent to explore a new and efficient mercury removal technology for coal-fired power plants. A new acid-assisted electrochemical oxidation (AEO) technique for mercury removal was proposed using platinum plate as cathode and fluorine-doped tin dioxide (FTO) glass as anode. The effects of acid type, acid concentration, applied direct current (DC) voltage, electrolyte type, SO2, NO and O2 on the Hg0 removal efficiency were carried out. The results indicated that the mercury removal efficiency increased with the increase of DC voltage and nitric acid concentration. When the concentration of nitric acid increased to 0.15 mol/L, the mercury removal efficiency remained unchanged. SO2 and NO inhibited the removal of Hg0 in AEO system, but the inhibition was reversible. Compared with the mercury removal efficiency under single experimental conditions, the mercury removal efficiency of electrochemical oxidation can reach 96% under the experimental conditions of 0.1 mol/L nitric acid and 4V DC voltage, suggesting that the synergistic effect of nitric acid and DC voltage plays a key role. According to the experimental results, the mechanism of Hg0 removal in AEO system was analyzed. At the anode, Hg0 was oxidized by hydroxyl radical (OH) generated by the oxidation reaction on the anode surface. At the cathode, dissolved oxygen or O2 adsorbed on the surface of Pt is reduced to form anionic superoxide radicals (${\rm{O}}_2^- $). Moreover, parts of ${\rm{O}}_2^- $ would produce OH with the aid of electron at acidic condition. Free radicals capture experiments showed that O$_2^- $ and OH were the main active substances for the removal of Hg0 by acid-assisted electrochemical method. The research is helpful for the development of effective electrochemical techniques for industrial mercury removal and recycling of industrial acid waste.
A research paper
Study on the transformation behavior of Fe and Ca compounds in residue at different reaction space velocities
ZHANG Tao, WANG Xian-yuan, CUI Rui-li, YANG Xin-peng, ZHANG Long-li, ZHAO Yu-sheng, YANG Chao-he
 doi: 10.19906/j.cnki.JFCT.2023032
Abstract(27) HTML(54) PDF 1824KB(0)
For the oil samples from before and after fixed bed hydrogenation reaction at different space speeds, transformation behavior of iron and calcium compounds were studied. The oil samples were decomposed with acid and then extracted with aqueous alcoholic solution of sodium hydroxide, the corresponding petroleum acids derived from petroleum acid salts were obtained. The structure of petroleum acid was characterized by infrared spectrometry, element analysis, hydrogen nuclear magnetic spectrum, nuclear magnetic carbon and high resolution mass spectrometry. In order to study the transformation of petroleum acid in thermal reaction, the obtained petroleum acid was characterized by thermos-gravimetric mass spectrometry, the transformation process of petroleum acid in thermal reaction was analyzed, and then the transformation process of iron and calcium compounds in thermal reaction was obtained. The results show that the thermal oil acid residue before and after the modification of the main components in naphthenic acid, and exists in the form of polymer. Before and after the thermal modification process, petroleum acid is decomposed obviously, and the main products are CO2, C3H8 and other substances. With the increase of reaction depth, the degree of decarboxylation and chain breaking reaction of petroleum acid increases, so that the iron and calcium compounds in petroleum acid decomposition.
Comparative study on the performance of n-dodecane isomerization reaction on molecular sieve catalysts with different topological structures
LIU Jia, SONG Zhao-yang, LI Si-jie, ZHOU Ming-dong, LI Lei, LING Feng-xiang
 doi: 10.19906/j.cnki.JFCT.2023067
Abstract(4) HTML(2) PDF 3559KB(0)
The catalysts were prepared by loading the noble metal about 0.5% Pt with Y molecular sieves, ZSM-5 molecular sieves and β molecular sieves of similar Si/Al ratio, respectively, and the crystal structures of the molecular sieves with different topologies, elemental compositions, crystal structures, pore structures, activities, and Al distributions were investigated by means of XRD, XRF, TEM, N2 physical adsorption and desorption, NH3-TPD, Py-FTIR, and 27Al NMR. and Al distribution, and then investigated the effect of topology on the catalytic performance of n-dodecane isomerization reaction. The results showed that when the Si/Al ratios were close to each other, the ZSM-5 molecular sieve had the highest total acid and skeleton Al ratio and the smallest average pore size, the Y molecular sieve had the lowest total acid and skeleton Al ratio and the largest average pore size, and the β molecular sieve's total acid, skeleton Al ratio, and average pore size were between the two, which indicated that different topologies of the molecular sieves with different combinations of Si/Al atoms not only affected the structure of the pores and the size of the pore but also in the n-dodecane isomerization reaction, the Pt/ZSM-5 catalyst has the highest activity and the main reaction occurs on the outer surface without selectivity, the Pt/Y catalyst has the lowest activity and the isomerization reaction mainly occurs inside the pores, while the Pt/β catalyst has the activity between the two, and the isomerization reaction occurs at the pores and the key-locking reaction is dominant.
A research paper
Study on the effect of different metal oxides on the performance of cobalt-based Fischer-Tropsch catalysts
LI Bo-xiang, WANG Jun-gang, WANG Qiang, ZHANG Wei, LIU Yan, MA Zhan-cheng, MA Zhong-yi, HOU Bo
 doi: 10.19906/j.cnki.JFCT.2023018
Abstract(72) HTML(31) PDF 3769KB(8)
In this paper, three metal oxides, ZrO2, Al2O3 and MnO2, loaded with 1% content on hexagonal nanosheets of Co3O4 (NMS-Co), respectively, were prepared as reversed-phase catalyst models to investigate the effects of metal oxides on the performance of cobalt-based catalysts for Fischer-Tropsch synthesis. The results of H-TPD, CO-TPD and catalyst performance evaluation revealed that ZrO2 and Al2O3 could significantly increase the active sites of NMS-Co catalysts, lower the reaction temperature from 230 ℃ to 170 and 180 ℃, respectively, and increase the heavy hydrocarbon generation rate by 2.5 and 2 times, respectively, under the same conversion conditions. The CH4 selectivity was reduced from 37.8% to 3.6% and 12.0%, respectively. However, MnO2 increase the CO conversion only from 30.9% to 45.5% and decrease the CH4 selectivity to 16.5%. A new idea is proposed to investigate the effect of metal oxides on the performance of cobalt-based Fischer-Tropsch catalysts.
A research paper
Effect of Si/Al ratio of β zeolite on propane dehydrogenation without H2 over PtZn catalyst
LI Bo-nan, XING Ya-nan, KANG Lei-lei, LIU Xiao-yan
 doi: 10.19906/j.cnki.JFCT.2023023
Abstract(93) HTML(32) PDF 4556KB(14)
In this study, the PtZn/β-x catalysts (x refers to SiO2/Al2O3 mole ratio) were synthesized by co-impregnation method and the effect of Si/Al ratio of the β zeolite on propane non-hydrogen dehydrogenation was explored. A series of characterization such as XRD, BET, HAADF-STEM, NH3-TPD, C3H6-TPD were applied to investigate the phase structure, surface properties of catalysts, and their effects on the reaction performances. The results showed that, with the increase of Si/Al ratio, the catalytic stability would be enhanced following the order of PtZn/DeAl-β > PtZn/β-40 > PtZn/β-30 > PtZn/β-25, while the number of strong acid sites of the catalyst (PtZn/β-30 > PtZn/β-40 > PtZn/β-25 > PtZn/DeAl-β) was affected by the Si/Al ratio to some extent, which was opposite to the order of the propylene selectivity. Therefore, the control of the Si/Al ratio of zeolite is very important for optimizing the properties of the catalysts for propane dehydrogenation reaction. The catalysts with few strong acid sites, weak adsorption of propylene and large specific surface area are contributed to higher propane conversion, propylene selectivity and catalytic stability.
A research paper
Preparation and bifunctional photocatalytic properties of Mo-doped Zn0.5Cd0.5S assisted by Ti3C2
NIU Jie, WANG Liang, LI Chun-hu
 doi: 10.19906/j.cnki.JFCT.2023021
Abstract(51) HTML(30) PDF 9778KB(7)
Mo-doped Zn0.5Cd0.5S was prepared and compounded with Ti3C2 nanosheets by hydrothermal method. The crystal structure, surface composition, microscopic morphology, and photoelectric properties of the photocatalysts were analyzed by XRD, SEM, TEM, XPS, UV-vis DRS, fluorescence spectroscopy, transient photocurrent methods. The results show that the doping of Mo causes changes in the lattice structure of Zn0.5Cd0.5S, while the loading of Ti3C2 increases the photocatalytic active site and accelerates the electron transfer rate. The photocatalytic activity was investigated by degrading the tetracycline solution under visible light irradiation with simultaneous H2 production. The results showed that with the synergistic effect of Mo doping and loaded Ti3C2, the degradation rate of (Tetracycline)TC reached more than 70% within 60 min, while the H2 yield reached 883 μmol/(g·h). The radical capture experiments proved that the main active substance for degradation was holes and for H2 production was electrons.
A research paper
Preparation and Characterization of Ni modified MoS2 for Electrocatalytic Hydrogen Evolution
HAN Jia-qi, WU Hong-jun
 doi: 10.19906/j.cnki.JFCT.2022092
Abstract(201) HTML(166) PDF 4344KB(15)
Developing highly active and low cost hydrogen evolution electrocatalysts is expected to improve the efficiency of water electrolysis hydrogen production, achieve large-scale hydrogen production, and promote the development and utilization of hydrogen energy is imminent. Molybdenum disulfide (MoS2) has shown a certain potential in the field of hydrogen evolution catalysis, and its modification to improve the catalytic activity and replace the platinum-based catalyst has become a research hotspot in recent years. A simple one-step solvothermal method was used to successfully synthesize a Ni-doped electrocatalytic hydrogen evolution (HER) catalyst Ni@MoS2, which has excellent electrocatalytic hydrogen evolution activity and good stability. The 20Ni@MoS2 as prepared at 240 ℃ exhibits enhanced HER performance with a low overpotential of 190 mV at 10 mA/cm2 and Tafel slope of 162 mV/dec in acidic medium.
A research paper
Synthesis of propylene carbonate from CO2 catalyzed by supported imidazoles ionic liquids
HUA Shu-qing, WANG Jing-yun, SUN Jing, ZHOU Ming-dong
 doi: 10.19906/j.cnki.JFCT.2023027
Abstract(95) HTML(41) PDF 3255KB(15)
Carbon dioxide is one of the most main greenhouse gases causing the global warming, however, as a rich C1 resource, the high value utilization of CO2 has attracted wide attention. Cyclic carbonate is an excellent medium for batteries and capacitors and widely used in industrial production. Therefore, it is of great significance to convert CO2 into cyclic carbonate from the viewpoint of environmental protection and resource utilization. In this paper, we synthesized a series of imidazole heterogeneous catalysts supported on polystyrene resin, and the catalytic activity for cycloaddition reaction of CO2 in high pressure reactor has been studied. The results showed that PS-TBIM-PCIMBr2 exhibited the excellent and stable catalytic activity. PS-TBIM-PCIMBr2 was also used to prepare propylene carbonate in the continuous fixed-bed reactor and the yield of PC was still 91% after 500 h.
A research paper
Pyrolysis magnetization of low-rank coal and distribution characteristics of sulfur and heavy metals in char products
GAO Min, CHU Mo, YANG Yan-bo, HÜ Jia-bao, LÜ Fei-yong, WANG Hao-yang
 doi: 10.1016/S1872-5813(23)60359-7
Abstract(106) HTML(42) PDF 18304KB(11)
The distribution of sulfur and heavy metals in char of Gansu lignite and Shanxi subbituminous coal was studied by means of pyrolysis and magnetic separation at different pyrolysis temperatures. The contents of sulfur and heavy metal elements in char were analyzed and determined by ICP-OES and ICP-MS, and the mineral composition and apparent morphology of char were characterized by XRD and SEM-EDS. The results show that the highest desulfurization rates of Gansu lignite and Shanxi Subbituminous coal can reach 52.37% and 17.54% respectively under optimal conditions. This is related to the phase transition behavior of pyrite during pyrolysis. The desulphurization rate of Shanxi subbituminous char is lower than that of Gansu lignite char mainly because the occurrence and inclusion of associated minerals and the organic matter influence the transformation of pyrite during pyrolysis. Ni and Cr have a strong affinity with Fe–S minerals, which are enriched into magnetic char with sulfur. At 800 ℃, Cr content in magnetic char of Gansu coal and Shanxi coal is 8698.25 and 32327.47 µg/g higher than that in non-magnetic char, respectively. The pyrolytic magnetization of low-rank coal and the distribution of sulfur and heavy metals in its char products provide data support and a new idea for the removal of sulfur and heavy metals from coal.
A research paper
Controllable Preparation of Wrapped Fe2O3@rGO Composites and their Lithium Ion Storage Performance
QI Hui, WANG Rui, WANG Wen-jing, HAN Hong-fei
 doi: 10.1016/S1872-5813(23)60380-9
Abstract(6) HTML(1) PDF 32591KB(2)
In this paper, reduced graphene oxides wrapped hollow Fe2O3 spheres (Fe2O3@rGO) are successfully prepared by solvothermal method. Results show that plenty of Fe-O-C bonds between reduced graphene oxides and Fe2O3, significantly improve electron transfer rate of the composite anodes; and confinement effect of reduced graphene oxides slows the pulverization rate of Fe2O3 during charge/discharge process. As expected, wrapped structured Fe2O3@rGO anode exhibits high rate capability of 514 mAh g−1 at high current of 5.0 A g−1 and durable cycling life over 500 cycles with a capacity of 987 mAh g−1 under 0.5 A g−1 with a capacity retention of 81.1%. This work provides an effective strategy for the preparation of high-rate and long-life graphene composite anode materials.
Hydrogen generation from hydrous hydrazine over Rh/g-C3N4 nanocatalysts
QIU Xiao-kui, SUN Jia-li, HUA Jun-feng, ZHENG Jun-ning, WAN Chao, XU Li-xin
 doi: 10.19906/j.cnki.JFCT.2022093
Abstract(162) HTML(73) PDF 6870KB(9)
In this paper, g-C3N4 obtained by calcining melamine at high temperature in static air was used as the carrier, and the precious metal Rh was used as the active component. The Rh nanoparticles were supported on the g-C3N4 support by a simple impregnation reduction method to prepare high activity and high selectivity. Various characterization methods were used to study the microstructure and composition of the catalyst. In addition, the effect of reaction temperature and NaOH concentration on the catalytic decomposition of hydrous hydrazine was also investigated. The results show that the excellent catalytic activity of the catalyst stems from the fact that the g-C3N4 support provides anchor sites for the metal Rh and the support and the strong metal-support interactions. The catalytic activity of the catalyst increases with the increase of the reaction temperature, and the Rh/g-C3N4 catalyst has the highest catalytic activity when the NaOH concentration is 0.75 mol/L. The Rh/g-C3N4 catalyst has an activation energy of 30.7 kJ/mol and TOF value of 1466.4 h−1 for catalyzing the decomposition of hydrous hydrazine for hydrogen production. After 5 cycles, the catalyst still maintains a good catalytic activity, indicating that the catalyst has a good cyclic stability.
A research paper
Morphology study of nickel and vanadium in asphaltenes via hydropyrolysis
ZHENG Fang, WANG Yan-bin, HUO Da, WANG Chun-yan, CAO Qing, HE Jing, SHI Quan
 doi: 10.1016/S1872-5813(23)60333-0
Abstract(108) HTML(60) PDF 758KB(11)
The morphology of nickel and vanadium compounds in the asphaltenes were investigated via hydropyrolysis with the help of inductively coupled plasma mass spectrometer (ICP MS), ultraviolet-visible (UV-vis), high-temperature gas chromatography atomic emission detection (HT GC-AED), and positive-ion electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry (+ESI FT-ICR MS). The results showed that the toluene soluble yields of products decreased from 64% to 19% as the hydropyrolysis temperature increased from 330 to 410℃, while the abundance of nickel and vanadium compounds detected by GC-AED increased significantly. The molecular composition distribution of nickel and vanadyl porphyrins showed rhythmic changes in the hydropyrolysis treated asphaltenes with different temperatures.
A research paper
Role of Ga in promoting epoxidation of cis-cyclooctene over Ga-WOx/SBA-15
LI Peng-hui, WANG Hui-xiang, LI Jun-fen, LÜ Bao-liang
 doi: 10.1016/S1872-5813(23)60350-0
Abstract(111) HTML(20) PDF 2401KB(10)
This article investigates the promoting effect of gallium (Ga) on the activity of Ga-WOx/SBA-15 catalyst for cis-cyclooctene epoxidation with H2O2. The optimal catalyst of 0.3Ga-WOx/SBA-15 offered a turnover frequency (TOF) of 112 h–1, which was nearly two times than that of WOx/SBA-15 (57 h–1). The low apparent reaction activation energy for 0.3Ga-WOx/SBA-15 (49.6 kJ/mol vs 64.0 kJ/mol for WOx/SBA-15) was also in line with its superior performance. Kinetic analysis demonstrated stronger adsorption of H2O2 on 0.3Ga-WOx/SBA-15 surface, facilitating the H2O2 activation. Based on the characterizations and catalytic performance, the improvement of Ga was attributed to the increase of Lewis acid sites and the enhancement of electrophilicity. Furthermore, the metal hydrogen peroxide (M-OOH) was identified as the primary intermediate.
A research paper
Study on effect of fufural residue on fusion characteristics of gasification coal ash
MA Xiao-tong, WANG Zhi-gang, LU Hao, ZHUANG Shu-juan, WANG Yan-xia, LIU Wei, ZHAO Jiang-shan, KONG Ling-xue
 doi: 10.1016/S1872-5813(23)60355-X
Abstract(120) HTML(105) PDF 11704KB(4)
A typical furfural residue and two gasification coal with different ratio of silicon and aluminum (Si/Al) were selected in the study. The effect of furfural residue on fusion temperature of gasification coal ash were investigated. X-ray diffraction instrument (XRD) was used to measure mineral evolution of co-gasification ash at different temperatures. The phase change in equilibrium state was calculated by the software FactSage. The results show that with the increase of furfural residue ratio, the fusion temperatures of both gasification coal ash firstly increased and then decreased, and the increase trend of SA with high Si/Al ratio was more significant. When furfural residue was added, the high-melting mineral of gasification slag was changed from anorthite (CaAl2Si2O8) to leucite (KAlSi2O6) which was still present as solid phase at 1300 ℃. This resulted in the increase of ash fusion temperatures. SA has more amount of SiO2 than QA, which can reacted with K2O to produce more leucite (KAlSi2O6) with higher melting point. This caused the ash fusion temperatures to rise. With the ratio of furfural residue continuing to increase, and then ash fusion temperatures decreased. It is the reason that kaliophilite(KAlSiO4) with low-melting point was generated with the content of K2O increasing.
A research paper
Electronic modulation and synergistic effect on Fe-doped NiSe@NiS composites to improve oxygen evolution performance
YIN Xue-li, DAI Xiao-ping
 doi: 10.1016/S1872-5813(23)60374-3
Abstract(36) HTML(20) PDF 12270KB(6)
Fe-doped nickel selenide and nickel sulfide composites was in-situ grown on nickel foam (NF) substrate (Fe-NiSe@NiS/NF) by solvothermal method. Benefit from the optimized electron structure by Fe doping, the synergistic effect of NiSe@NiS and faster electron transfer, Fe-NiSe@NiS/NF exhibits excellent OER activity with the overpotential of 330 mV at 150 mA/cm2 in 1 mol/L KOH solution, and the voltage barely changed after 40 h of stability test.
A research paper
Support effects on Ru-based catalysts for Fischer-Tropsch synthesis to olefins
YAO Tai-zhen, AN Yun-lei, YU Hai-ling, LIN Tie-jun, YU Fei, ZHONG Liang-shu
 doi: 10.1016/S1872-5813(23)60351-2
Abstract(89) HTML(28) PDF 23693KB(22)
The effects of supports (CeO2, ZrO2, MnO2, SiO2 and active carbon) on the structure and catalytic performance of Ru-based catalysts for Fischer-Tropsch synthesis to olefins (FTO) were investigated. It was found that the intrinsic characteristics of supports and the metal-support interaction (MSI) would greatly influence the catalytic performance. The catalytic activity followed the order: Ru/SiO2 > Ru/ZrO2 > Ru/MnO2 > Ru/AC > Ru/CeO2. As far as olefins selectivity was concerned, both Ru/SiO2 and Ru/MnO2 possessed high selectivity to olefins (>70%), while olefins selectivity for Ru/ZrO2 was the lowest (29.9%). Ru/SiO2 exhibited the appropriate Ru nanoparticlessize ( ~ 5 nm) with highest activity due to the relative low MSI between Ru and SiO2. Both Ru/AC and Ru/MnO2 presented low CO conversion with Ru nanoparticles size of 1−3 nm. Stronger olefins secondary hydrogenation capacity led to the significantly decreased olefins selectivity for Ru/AC and Ru/ZrO2. In addition, partial Ru species might be encapsulated by reducible CeO2 layer for Ru/CeO2 due to strong MSI effects, leading to the lowest activity.
Progress in the thermo-catalytic hydrogenation of CO2 to ethanol
MAO Yu-zhong, ZHA Fei, TIAN Hai-feng, TANG Xiao-hua, CHANG Yue, GUO Xiao-jun
 doi: 10.1016/S1872-5813(22)60065-3
Abstract(463) HTML(273) PDF 8725KB(135)
The chemical conversion of CO2 is considered as one of the effective measures to reduce carbon emission, where breakthroughs have been made in the thermo-catalytic hydrogenation of CO2 to ethanol in recent years. However, the synthesis of ethanol from CO2 still suffers from some problems such as low ethanol yield and abundant by-products. In this paper, the research progress made in the thermo-catalytic hydrogenation of CO2 to ethanol was reviewed. The performance of various catalysts with zeolites, metal oxides, perovskites, silica, organic frameworks and carbon-based materials as the support was evaluated and the synergistic effect of different metals on the CO2 conversion and the intervention of various active species on the reaction were analyzed. Accordingly, the catalyst systems that can effectively promote the adsorption and activation of CO2 and the coupling of C–C bond were summarized. Finally, the appropriate conditions as well as possible reaction mechanism for the CO2 hydrogenation to ethanol were proposed. The insight shown in this paper should be beneficial to designing efficient catalysts, optimizing the reaction conditions and understanding the mechanism of CO2 hydrogenation to ethanol in the future.
Effect of H2O, SO2 and CO2 on PbO adsorption in CaO surface during sewage sludge combustion
SHI Yi-lin, HE Xue-fu, WANG Yan-lin, QIAO Xiao-lei, JIA Li, JIN Yan
 doi: 10.19906/j.cnki.JFCT.2023001
Abstract(85) HTML(24) PDF 8260KB(6)
The effect of flue gas components on the adsorption of PbO on the surface of CaO(001) during sewage sludge combustion was studied by DFT (Density Functional Theory). The calculation results show that O apex on the surface of CaO(001) is the active site of the adsorption of PbO molecules, H2O molecules, SO2 molecules and CO2 molecules. The presence of H2O molecules, SO2 molecules and CO2 molecules increased the adsorption energy of PbO molecules on the surface of CaO(001) by 71.42, 19.589 and 46.431 kJ/mol, respectively. OH group and local Ca(OH)2 surface structure formed by H2O molecules during the adsorption process are conducive to the adsorption of PbO molecules. Density of state orbitals of OS atom in SO2 molecule and Osurf atom on the surface of CaO(001) overlap with the orbitals of Pb atom, making the adsorption of PbO molecules on the surface more stable. CO3 group formed by CO2 molecules pre-adsorbed on the surface of CaO(001) has a strong adsorption effect on PbO molecules, making PbO molecules more stable adsorption on the surface of CaO(001).
A research paper
Directing the CdS nanosheet and nanowire to high efficiency for photocatalytic anaerobic dehydrogenation of benzyl alcohol to benzaldehyde by depositing Au25 nanoclusters
LI Xing-chi, ZHAO Han, PAN Xiao-li, SU Yang, LI Ren-gui, WANG Hua, KANG Lei-lei, LIU Xiao-yan
 doi: 10.1016/S1872-5813(23)60373-1
Abstract(38) HTML(18) PDF 4911KB(6)
The photocatalysis of direct dehydrogenation of benzyl alcohol to benzaldehyde is an energy saving way to synthesize fine chemicals and pure hydrogen by using solar energy. The CdS-based catalysts were one of the typical kinds of photocatalysts for this reaction. The morphology of CdS could be easily tuned, which could greatly influence the photocatalytic performances. However, the morphology effect of CdS on the photocatalytic behaviour of the direct dehydrogenation of benzyl alcohol has not been investigated yet. In this work, we synthesized CdS with two different morphologies (nanosheet (NS) and nanowire (NW)) and found the CdS-NS showed much higher photocatalytic activity for converting the benzyl alcohol than the CdS-NW, but the selectivity to benzaldehyde over the two supports was very low. By depositing Au25 nanoclusters on the CdS-NW and CdS-NS, the morphology effect of the CdS support could be mitigated and their catalytic activity and selectivity could be greatly boosted for the photocatalytic anaerobic dehydrogenation of benzyl alcohol to benzaldehyde and H2. The results of this work would provide new insight into the design of efficient photocatalysts for synthesizing fine chemicals.
A research paper
Investigation of the promotion effect of metal oxides on the water-gas shift reaction activity over Pt-MOx/CeO2 catalysts for aqueous phase reforming
ZHANG Wei-jie, TIAN Zhi-peng, HUANG Jia-hao, WANG Jun-yao, LUO Xiang-long, WANG Chao, SHU Ri-yang, LIU Jian-ping, CHEN Ying
 doi: 10.1016/S1872-5813(23)60363-9
Abstract(56) HTML(61) PDF 3286KB(11)
Aqueous phase reforming (APR) of methanol is a potential pathway for the effective hydrogen production under relatively mild conditions. The Pt/CeO2 and a series of Pt-MOx/CeO2 (M = Fe, Cr, Mg, Mn) catalysts were prepared by sequential impregnation method and their APR reaction performances were studied. The catalyst properties including valence state of the promoters, the amount of oxygen vacancies, the metal distributions, the adsorption properties of CO and the acidity/basicity of catalysts were characterized and analyzed by XPS, XRD, TEM, CO-TPD, NH3-TPD, CO2-TPD, etc. It was found that the addition of MOx weakened the Pt-CeO2 interaction and promoted the generation of Ptδ + species with lower valence state, which contribute to the C–H bond cleavage and facilitate methanol conversion. The highest hydrogen production (164.78mmol) and relatively low CO and CH4 selectivities were obtained over the Pt-MgO/CeO2, while the highest CH4 selectivity was obtained over the Pt-CrOx/CeO2 (2.21%).Over the Pt/CeO2 and Pt-MOx/CeO2 (M = Fe, Cr, Mg, Mn) catalysts, CO2/CH4 ratio correlated well with the catalyst basicity, indicating that the basicity promotes the dissociation adsorption of H2O as well as the water-gas shift (WGS) reaction activity and decreases the methanation activity.
A research paper
Effect of Fe2O3 on ZrTiO4 support for NH3-SCR catalytic performance
YUAN Long-teng, HU Ping, HU Bo-liang, HAN Jia-yu, MA Sheng-jie, YANG Fan, Alex A. Volinsky
 doi: 10.1016/S1872-5813(23)60377-9
Abstract(48) HTML(15) PDF 12620KB(9)
The selective catalytic reduction (SCR) NH3 catalyst is mainly used in industrial production and automobile exhaust cleaning. In this study, a novel α% Fe2O3/ZrTiO4 (α=0%, 8%, 12%, 15%) catalyst was prepared by the coprecipitation impregnation method. The results show that the NOx conversion rate of 12% Fe2O3/ZrTiO4 catalyst with the optimal composition is high above 80% at 250−400 °C, close to 100% at 300 °C, and N2 selectivity is high above 90% at 200−450 °C. The redox properties, surface acidity, and Oβ/(Oα + Oβ) ratio of ZrTiO4 catalysts are improved after loading Fe2O3 on the ZrTiO4 surface, which is attributed not only to the porous structure of α% Fe2O3/ZrTiO4 catalyst but also to the synergistic interaction between the active component Fe2O3 and the support ZrTiO4. In addition, in-situ DRIFT reactions show that the NH3-SCR reaction of 12% Fe2O3/ZrTiO4 catalyst follows the Eley-Rideal mechanism. A clear reaction mechanism is conducive to a deeper understanding of the reaction process of NOx conversion during SCR. This work provides a feasible strategy for Fe-based SCR catalysts to replace V-based catalysts in the medium temperature range in the future.
A research paper
Deactivation of Cu/SiO2 catalyst in gas-phase hydrogenation of furfural to furfuryl alcohol
Yu Dong-dong, Yu Xin-rui, Zhang Ya-jing, Wang Kang-jun
 doi: 10.1016/S1872-5813(23)60362-7
Abstract(132) HTML(55) PDF 7634KB(14)
The Cu/SiO2 catalysts were prepared by co-precipitation method. The catalytic hydrogenation of furfural to furfuryl alcohol was evaluated in a fixed bed reactor. The Cu/SiO2 catalysts were characterized by H2-TPR, ICP-OES, XPS, TG, Raman and TEM. The deactivation mechanism of Cu/SiO2 catalyst in the reaction was investigated. Under the conditions of atmospheric pressure, reaction temperature of 140 ℃, mass space velocity of 2.4 h−1 and the molar ratio of hydrogen to furfural of 9.7, the furfural conversion was higher than 97% in the first 5 h reaction. The conversion of furfural decreased rapidly from 96% to 32% during reaction time from 6 to 21 h, indicating that Cu/SiO2 catalyst was rapidly deactivated. The factors for the deactivation of Cu/SiO2 catalyst were the agglomeration and sintering of the active component copper and the carbon deposition on the catalyst surface, resulting in the active site Cu0 was covered.
Study on performance and mechanism of CuMn2O4/MO2 sup-ported catalyst for simultaneous removal of toluene and NOx
LIU Xu, HUANG Yan, ZHAO Ling-kui, LI Si-mi, TAO Hong-fan, RAO Si-min, ZHU Hong
 doi: 10.19906/j.cnki.JFCT.2023024
Abstract(85) HTML(46) PDF 2690KB(8)
In this study, CuMn2O4/MO2(M=Mn, Ti, Ce) catalysts with different support loads were prepared by sol-gel spontaneous combustion at low temperature, and the removal performance of toluene and NOx was evaluated. The results showed that the addition of CeO2 carrier could significantly alleviate the mutual inhibition of toluene oxidation and NH3-SCR over CuMn2O4. Therefore, CuMn2O4/CeO2 catalyst showed the best removal efficiency of toluene and NOx simultaneously. The physicochemical properties of the catalyst and the reaction mechanism of CuMn2O4 were analyzed by BET, XRD, NH3-TPD, O2-TPD and combined XPS and in-situ DRIFTs. The results showed that the introduction of CeO2 increased the proportion of Mn4 + /Mnn + in the catalyst, and promoted the formation of rich acid sites and oxygen vacancies on the surface of CuMn2O4/CeO2 catalyst. In addition, the strong interaction between Cu, Mn and Ce accelerated electron transfer and enhance the redox cycle for Cu + + Ce4 + ↔Cu2 + + Ce3 + 、Mn4 + + Ce3 + ↔Mn3 + + Ce4 + . It has been confirmed by In-situ DRIFTs that NH3-SCR reaction on CuMn2O4 catalyst follows Langmuir-Hinshelwood mechanism and oxidation of toluene follows Mars-van Krevelen mechanism. Therefore, CuMn2O4/CeO2 catalyst with CeO2 as the support has excellent reoxidation ability to promote the complete oxidation of toluene, so it shows excellent removal ability of toluene and NOx simultaneously. This work can provide guidance for the development of catalysts for simultaneous removal of toluene and NOx.
A research paper
Green synthesis of Mesoporous Carbon Supported (Ni)MoS2 as Efficient Hydrodesulfurization Catalyst
LIANG Ji-lei, WU Wen-jie, WU Meng-meng, HUA Jia-wei, LIU Yun-qi, LIU Chen-guang
 doi: 10.19906/j.cnki.JFCT.2023033
Abstract(61) HTML(67) PDF 11047KB(12)
Mesoporous carbon supported Ni–Mo hydrodesulfurization (HDS) catalysts have been successfully prepared with Anderson polyoxometalate (NH4)4[NiMo6O24 H6]·5H2O, thiourea, citric acid, and sodium chloride to evaluate the HDS performance with dibenzothiophene. The catalysts were prepared by one–step vacuum freeze–drying, followed by calcination under nitrogen and washing off the template, and then structurally characterized via many devices, including XRD, Raman, low temperature N2 adsorption–desorption isotherm, SEM, HRTEM, XPS, and TPR. The results show these catalysts possess weaker metal–support interaction, shorter MoS2 particles (4.9 nm) and appropriate stacking number (4.8), and higher percent of NiMoS active phase. The dibenzothiophene conversion, overall pseudo–first order rate constant and the turnover frequency can reach 94.1%, 1.7 × 10–6 mol/(g·s) and 2.8 × 10–3 s–1, respectively. By using in situ formed NaCl and H2S as hard template and sulfidizing agent respectively, this methodology opens a new avenue for the simple and environmental friendly fabrication of HDS catalysts via the synchronization and riveting of mesoporous carbon support and MoS2 particles.
Research progress of the typical ironmaking processes with the direct participation of biomass and the related formation mechanism of pollutants
WANG Zi-qi, MA Hao-fei, YUAN Peng, SHEN Bo-xiong, WU Bing-qiang, ZHANG Wei-li
 doi: 10.19906/j.cnki.JFCT.2023015
Abstract(151) HTML(98) PDF 4336KB(18)
The application of renewable and clean resources to replace fossil resources such as coal and coke in ironmaking is one of the most important ways for iron and steel companies to achieve "carbon neutrality" and "carbon peaking". Biomass resources such as agricultural and forestry wastes have received a lot of attention in ironmaking because of their low cost and availability, low temperature reducibility and carbon neutrality. In this work, the reaction mechanism, gaseous products and pollutant release characteristics are analyzed in a more systematic way, focusing on the two main thermal utilization methods of biomass, namely pyrolysis and combustion. Subsequently, the process overview, process analysis and pollutant generation mechanism are discussed in detail, by taking blast furnace blowing biomass fuel and biomass reductant for direct reduction ironmaking as representatives. Finally, an economic analysis of the above typical processes based on the utilization of biomass in ironmaking is carried out, as well as an outlook of emission reduction strategies, with a view to providing valuable references for alleviating the contradiction between fossil energy supply and demand, reducing emissions from ironmaking and even the transformation and upgrading of iron and steel industry.
A research paper
In-situ catalytic pyrolysis of pine powder by ZnCl2 to bio-oil under mild conditions and application of biochar
PANG Zhao-bin, WANG Jian-gang, CUI Hong-you, WANG Jing-hua
 doi: 10.1016/S1872-5813(23)60344-5
Abstract(126) HTML(17) PDF 2174KB(8)
Fast pyrolysis of biomass is an effective way for biomass conversion and utilization. However, the pyrolysis temperature is usually high because it is a non-catalytic process, resulting in the complicated composition of bio-oil and difficulty to control. Aiming to explore in-situ catalysis in this paper, the fast pyrolysis of lignin, cellulose, corncob and pine wood powder was studied using ZnCl2 as the catalyst. The activation energies of non-catalytic pyrolysis and catalytic pyrolysis were obtained based on kinetic fitting of their thermal gravimetric curves. The variation in pyrolysis oil composition was analyzed. It was found that ZnCl2 in-situ catalysis could not only significantly reduce the pyrolysis temperature, but also simplify the resultant bio-oil composition. Even under pyrolysis temperature as low as 350 ℃, fast pyrolysis of pine wood powder could achieve a yield of 47% of bio-oil, which was predominantly composed of the derivatives of cellulose and hemicellulose. ZnCl2 in-situ catalysis could significantly decrease the activation energy of cellulose cracking from 304.78 to 112.46 kJ/mol, but has little effect on that of lignin. The carbon residue from ZnCl2-catalyzed pyrolysis was further carbonized at 600 ℃, affording activated carbon with adsorption capacity of phenol up to 165 mg/g. The research work provides guidance and reference for the development of in-situ catalytic pyrolysis technology with high efficiency.
A research paper
Relationship between fluorescence characteristics of coal macerals and excitation time
ZHANG Ya-ru, BAI Jin-feng, JIN Li-jun, LI Yang, HU Hao-quan
 doi: 10.1016/S1872-5813(23)60339-1
Abstract(127) HTML(20) PDF 2289KB(5)
The fluorescence characteristics of coal macerals can be used as one of the indexes to evaluate the properties of coking coal. In this work, a single-wavelength laser with a wavelength of 360 nm was used as the excitation source to excite the surface of particulate block under a polarizing microscope. Effect of excitation time on fluorescence characteristics of the macerals was studied. The relationship between spontaneous fluorescence intensity and the excitation time of each maceral of six kinds of coking coals show that the fluorescence characteristics of coal macerals are related to the type and metamorphism of coal. The excitation time has a certain effect on the fluorescence parameters of the macerals. By comparing the relative fluorescence intensity values under different excitation times, it is found that the mean relative fluorescence intensity within 15 s can be used as an optical parameter to characterize the structure and metamorphic grade of different macerals. The essence of this method is to express movement of electrons in outer layer of nucleus by macroscopic fluorescence spectrum and relative fluorescence intensity of the initial state value and simplify microscopic complexity into macroscopic and numerical form generally accepted.
A research paper
Preparation of the PdAg/CDs composite and its catalytic performance in the hydrogenolysis of glucose
CHEN De-quan, WANG An, BAO Gui-rong, GAO Peng, LUO Jia, JI Xue-wu, DENG Wen-yao, LIU Li
 doi: 10.1016/S1872-5813(23)60340-8
Abstract(107) HTML(30) PDF 2136KB(11)
With carbon dots (CDs) as the reducing agent and support, a PdAg/CDs composite catalyst was prepared by simple light reduction method. The results of XRD, TEM, FT-IR and XPS characterization indicate that the PdAg/CDs composite has an average particle size of about 10.45 nm, where Pd and Ag exist on the surface of CDs mainly in the alloy form of zero valence. The catalytic performance of the PdAg/CDs composite was evaluated in the hydrogenolysis of glucose in water. The results illustrate that the PdAg/CDs composite catalyst is highly active in the glucose hydrogenolysis; after reaction for 3 h under 140 °C, 4 MPa of initial H2 pressure, 100 mg of glucose and 25 mg of catalyst, the conversion of glucose is 68.85% and the yield of acetol reaches 8.36%.
A research paper
Advances in heterogeneous catalytic C−H bond carbonylation of alkynes with CO2
WU Jie-wen, FU Hui-yu, CHEN Xiao, LIANG Chang-hai
 doi: 10.19906/j.cnki.JFCT.2023002
Abstract(267) HTML(127) PDF 10207KB(35)
The carboxylation of C−H bond of terminal alkyne with CO2 to propargylic acid compounds conforms to the concept of green chemistry, which plays an important role in the field of organic and pharmaceutical intermediate synthesis. Under the background of "Carbon peaking and carbon neutrality", this reaction is also an effective way to realize the high value utilization of CO2. At present, this reaction system is mainly carried out through homogeneous catalysis. However, due to the advantages of heterogeneous catalysis system such as easy separation and recovery, heterogeneous catalytic C−H bond carbonylation of alkynes with CO2 has also gradually attracted attention. Based on the activation mechanism of C−H bond and CO2, relevant research has been carried out over coin metal catalysts. Through the synergistic effect of coin metal and carrier, the coupling of C−C bond is promoted to achieve the synthesis of propargylic acid compounds. In this paper, the heterogeneous catalytic C−H bond carbonylation of alkynes with CO2 is systematically reviewed. The activation of the system, the mechanism of carboxylation reaction, and the structural characteristics of the catalyst are analyzed and summarized, which provides a research idea for the development of efficient heterogeneous catalyst for carboxylation and related processes.
A research paper
Ultrathin MXene nanosheets for electrocatalytic hydrogen evolution under alkaline condition
DUAN Xiao-hui, LIU Yan, WU Shi, CHEN Xi, YANG Yan-yan, YU Zhong-liang
 doi: 10.19906/j.cnki.JFCT.2023010
Abstract(167) HTML(26) PDF 7151KB(25)
MXene (Ti3C2Tx) was prepared by etching MAX (Ti3AlC2) raw material and then ultrathin MXene nanosheets (MXene-NS, namely Ti3C2Tx-NS) was fabricated by using exfoliating method. The morphology, structure and elemental composition of the MXene-NS were investigated by scanning electron microscopy (SEM), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). The electrocatalytic hydrogen evolution reaction (HER) properties of MAX, MXene and MXene-NS were compared by electrochemical tests. The results revealed that compared with MAX and MXene, in 1 mol/L KOH, MXene-NS exhibited the lowest overpotential (190 mV@ −10 mA/cm2), the smallest Tafel slope (168 mV/dec), the smallest charge transfer resistance and the largest electrochemical active surface area. In addition, MXene-NS displayed a good potential response vs. current density. Furthermore, after long-term durability test, the polarization curve of MXene-NS was not notably decayed, which demonstrated the excellent stability for hydrogen evolution. All these results indicated that the exfoliation of MXene can effectively improve its electrocatalytic performance and the as-exfoliated MXene-NS is an excellent alternative for replacing the noble metal catalysts.
A research paper
Effect of operating conditions on release and transformation of sodium during CFB gasification of Zhundong coal
YANG Zi-jian, GUO Shuai, WANG Xiao-fang
 doi: 10.1016/S1872-5813(23)60348-2
Abstract(72) HTML(25) PDF 1133KB(9)
To provide some useful suggestions to the operation of circulating fluidized bed (CFB) gasifier, the effect of gasification temperature, residence time and agent on the release and transformation of sodium was studied by using a fixed bed reactor combined with Factsage software. The results indicated that gasification temperature was the significant factor to the release and transformation of sodium. For the promoting effect of sodium release, it was ascribed to the intense of sodium volatilization and competitive reaction between lime and meta-kaolin. Meanwhile, the high temperature promoted the formation of nepheline and slag. The threshold temperature of latter was near 950 °C. It was interesting to find that the release of sodium could be divided into two stages: coal pyrolysis and char gasification. In coal pyrolysis, part of organic and water-soluble sodium was released. The remainder either combined with char structure, or reacted with minerals. In char gasification, Sodium, combined with char structure, was released along with char gasification. Due to the decrease of melting temperature and the formation of NaOH, steam showed a promoting effect on the sodium release. Oppositely, oxygen and nitrogen presented an inhibiting effect. The former was ascribed to the formation of Na2SO4, while the latter was caused by the chemical binding and physical wrapping effect of char.
Effect of silicon oxide additive on the transformation characteristics of sodium and sulfur in Zhundong coal ash under atmospheric and elevated pressure
XIAO Wu-yang, WEI Bo, WANG Jian-jiang, MA Jin-rong, ABUDOUREHEMAN Maierhaba, LI Xian, YAO Hong, CHENG Ze-ning
 doi: 10.1016/S1872-5813(23)60353-6
Abstract(64) HTML(18) PDF 1121KB(8)
The effects of silicon oxide additive on the transformation characteristics of sodium and sulfur in coal ash under atmospheric and elevated pressure were investigated in this study. The results indicated that silicon oxide additive significantly inhibited the release of sodium under high pressure. The sodium content in ash with 4% of silicon oxide additive was 3.5% at 0.1 MPa, which was higher than that without additive. However, the sodium content increased to 5.4% without additive and 6.9% with 4% additive at 4 MPa, respectively. The sodium mainly existed in the forms of NaAlSiO4 and NaAlSi3O8 at 0.1 MPa, and the content of NaAlSiO4 increased with increasing additive dosage, which weakened the agglomeration of ash. The decomposition of low melting point mineral CaSO4 was inhibited at 4 MPa, and the formation of Na6Ca2Al6Si6O24(SO4)2 from NaAlSiO4 and CaSO4 was promoted significantly with increasing additive dosage. Furthermore, the inhibition mechanism of sodium and sulfur released from coal ash by silicon oxide under high pressure was proposed.
A research paper
Plasmon-enhanced Photocatalytic Selective Hydrogenation of Phenylacetylene over Ni/TiO2 Catalysts
WANG Jing, WANG Rui-yi, ZHANG Jin, LI Xin-cheng, WANG Yun-wei, ZHENG Zhan-feng
 doi: 10.19906/j.cnki.JFCT.2023042
Abstract(153) HTML(54) PDF 7959KB(32)
Itis a great challenge for the selective hydrogenation of phenylacetylene to styrene over non-noble metal catalyst under mild reaction conditions. Carbon-modified TiO2 supported nickel nanoparticles catalyst was prepared using impregnation-reduction method, which exhibited excellent photocatalytic performance in selective hydrogenation of phenylacetylene under visible light irradiation. The photo-excited hot electrons over Ni nanoparticles promoted the activation of reactants. The electron-rich Ni nanoparticles inhibit the adsorption of phenylethylene on the surface of Ni/TiO2, which increased the selectivity of phenylethylene. This work provides an environmentally-benign and efficient method for photocatalytic hydrogenation of phenylacetylene.
A research paper
Adsorption equilibrium of methane on activated carbon and typical kinds of MOFs
GUO Dong, LI Shan-shan, WANG Hu, ZHENG Qing-rong
 doi: 10.1016/S1872-5813(23)60364-0
Abstract(54) HTML(19) PDF 1188KB(7)
The accuracy of the adsorption model in predicting equilibrium data is crucial to the further design of the adsorption system. To develop adsorbents suitable for the storage of natural gas by adsorption, activated carbon SAC-02, HKUST-1 and MIL-101(Cr) were selected and synthesized. The prepared samples were undergone structural morphology observation, structure characterization by measuring adsorption isotherm of nitrogen at 77.15 K, analysis of adsorption equilibrium of methane on the samples by measuring adsorption isotherms at the temperature-pressure range at 293.15−323.15 K and 0−4 MPa. The accuracies of the results predicted by the Toth equation, the D-A equation and the Ono-Kondo equation were compared, adsorption performances of the samples were finally evaluated as per the values of the isosteric heat of adsorption and the densities of the adsorbed phase. Results show that the data predicted by the Toth equation have the smallest relative errors in comparing with those from the D-A equation and the Ono-Kondo equation. Results also reveal that the value of the mean isosteric heat of methane adsorption on the MIL-101(Cr) is the largest, and the densities of the adsorbed phase of methane are smaller than that of the liquid methane but increase with the equilibrium pressure. It suggests that the MIL-101(Cr) is more suitable for methane adsorption than the activated carbon and the HKUST-1, and Toth equation can be selected for adsorption equilibrium analysis on adsorbed natural gas system.
A research paper
Performance study of Pt-CeO2/ZSM-22 catalyzed n-heptane isomerization reaction
LI Zi-xin, XI Hong-juan, CHEN Xiao-yan, MA Zhong-yi, JIA Li-tao, LI De-bao, HOU Bo
 doi: 10.19906/j.cnki.JFCT.2023031
Abstract(127) HTML(42) PDF 6491KB(16)
A combination of impregnation and physical mixing methods was used to modulate the sites of the metal active center Pt, which were individually settled onto ZSM-22 molecular sieves or cerium oxide carriers, resulting in Pt-ZSM-22/CeO2 catalysts with atomic–level contacts at the spacing of the metal–acid bicenter sites and Pt-CeO2/ZSM-22 catalysts that maintained nanoscale spacing, respectively. The physical and chemical properties of the two catalysts were characterized by means of spherical differential electron microscopy, XRD, BET, H2-TPR and XPS, and their n-heptane isomerization reaction performance was investigated. In addition, the changes of the physicochemical properties and reaction performance of Pt-CeO2/ZSM-22 catalysts at different reduction temperatures were investigated. The results showed that the metal–acid center maintained nanoscale spacing Pt-CeO2/ZSM-22 catalyst had higher n-heptane isomerization activity and isomeric hydrocarbon yield, which could be attributed to the atomic–level dispersion of Pt on the CeO2 carrier. During the reduction of Pt-CeO2/ZSM-22 catalyst, the release of more oxygen vacancies from the CeO2 carrier helps to retard the aggregation of metal Pt and facilitates the adsorption of heptane molecules. When the reduction pretreatment temperature was 300 ℃, the heptane conversion and heptane isomerization hydrocarbon yield were 79.2% and 75.4%, respectively, and the isomerization selectivity reached 95.2%.
A research paper
Experimental study of Fe modified Mn/CeO2 catalyst for simultaneous removal of NO and toluene at low temperature
HAO Ze-rong, FENG Shuo, XING Yu-ye, SHEN Bo-xiong
 doi: 10.1016/S1872-5813(23)60358-5
Abstract(48) HTML(103) PDF 11768KB(6)
A series of Mn/CeO2 catalysts modified with different Fe contents were prepared by impregnation method and tested for their performance in the low temperature range for simultaneous de-nitrification and toluene removal. It was found that the Fe5Mn/CeO2 catalyst showed the best catalytic performance and the conversion efficiency of toluene reached 90% at 175 ℃ and NO conversion reached 90% at 95–300 ℃. The physical and chemical properties of the catalysts were characterized by BET, SEM, XRD, XPS, H2-TPR, NH3-TPD and O2-TPD. XPS results showed that the increased content of Ce3 + and Mn4 + in the Fe5Mn/CeO2 catalyst promoted the formation of oxygen vacancies and unsaturated chemical bonds, providing more active sites, thus facilitating the efficient removal of NO and toluene at low temperatures. Compared with other catalysts, H2-TPR, NH3-TPD and O2-TPD indicate that Fe5Mn/CeO2 catalyst has great redox ability, stronger acidity and better oxygen migration ability. In addition, this paper explores the effects between selective catalytic reduction (NH3-SCR) and catalytic oxidation reaction of toluene over Fe5Mn/CeO2 catalyst were investigated. NH3 preferentially reacts with the active site on the catalyst to inhibit the toluene oxidation process, while NO promotes the toluene removal process. Toluene can promote NH3-SCR process in a certain temperature range. While NO promotes the formation of NO2, NO2 effectively promotes the combination of toluene and active sites, which is conducive to the catalytic oxidation of toluene; The inhibition of toluene on the NH3-SCR process weakens with the increase of temperature. At 100 ℃, the inhibition of toluene on the NH3-SCR process disappears. When the temperature exceeds 225 ℃, toluene reacts with NO as a reducing agent and promotes the formation of NO2, thus promoting the NH3-SCR reaction.
A research paper
Kinetic analysis of biochar chemical looping gasification with calcium ferrite as oxygen carriers
GAO Pan, HUANG Xing-qi, LIU Yu-tong, ABULAITI Aikeremu, YANG Shao-xia
 doi: 10.1016/S1872-5813(23)60356-1
Abstract(117) HTML(52) PDF 11479KB(14)
The chemical looping gasification (CLG) kinetics of biochars with calcium ferrite as oxygen carriers and the effects of different kinds of calcium ferrite and biochars were investigated by TGA. The properties of the solid reactants were analyzed by XRD, SEM, BET, etc. The Škvára-Šesták method was used to determine the kinetic mechanism function. The results show that the reduction reaction rate and the oxygen carrying capacity of oxygen carriers follow the sequence: Ca2Fe2O5 > CaFe2O4 > Fe2O3, and CaFe2O4 > Ca2Fe2O5 > Fe2O3, respectively. The oxygen carriers can be completely reduced to Fe and CaO by biochar. The activation energy of CaFe2O4 reduction is in the range of 167.44–600.83 kJ/mol; and the activation energy of Ca2Fe2O5 reduction is in the range of 413.62–583.51 kJ/mol. The CaFe3O5 generated during the reduction of CaFe2O4 may have a negative influence on the lattice oxygen diffusion. The reduction of CaFe2O4 can be divided into two stages: when the conversion degree α is less than 0.15, the CaFe2O4 is reduced to Ca2Fe2O5 following the random nucleation and nuclei growth model; when α is greater than 0.15, Ca2Fe2O5 is further reduced to CaO and Fe following the 3-D diffusion mechanism. The mechanism function of the reduction of Ca2Fe2O5 is the same as that of the second stage of CaFe2O4 reduction.
A research paper
Preparation of PtCo/CNTs-C nanocatalysts and electrocatalytic oxidation performance of methanol
BAI Xue-li, QIU Hao-lei, ZHAO Zi-long, LIU Yu-cheng, WANG Feng, ZHANG Sheng-jian, ZHANG Xiao-ping
 doi: 10.19906/j.cnki.JFCT.2023043
Abstract(63) HTML(14) PDF 2444KB(3)
Using carbon nanotubes (CNTs) and XC-72R carbon black as the carrier, PtCo/CNTs-C catalyst with high electrochemical activity was prepared by impregnation reduction method. The structure of the catalyst was characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS). The material was used as a catalyst for methanol anodic oxidation, and the effects of different Co doping and temperature on the reaction were investigated. The results show that PtCo bimetallic alloy was formed in PtCo/CNTs-C nano-catalyst, and the alloy particles were relatively evenly distributed on the surface of the carrier. The introduction of carbon black and metal Co endowed the catalyst with higher catalytic activity. When the mass ratio of Pt∶Co was 94∶6, the catalyst had lower initial potential (−0.651V (vs SCE)) and higher current density (86.74 mA/cm2) for the catalytic oxidation of methanol, and the chronoamperometric test shows that the catalyst has good stability.
A research paper
The effect of crystal plane on Fe3O4 carbonization
LI Si-qi, WEI Xu-song, WANG Hong, QING Ming, SUO Hai-yun, LÜ Zhen-gang, GUO Hui-chuang, LIU Ying, YU Xin, YANG Yong, LI Yong-wang
 doi: 10.19906/j.cnki.JFCT.2023017
Abstract(124) HTML(94) PDF 3566KB(12)
In the Fischer-Tropsch synthesis reaction, Fe-based catalysts are widely used in large-scale indirect coal liquefaction industry due to their low price, high activity, and low CH4 selectivity. The catalytic performance is closely related to the catalyst particle size, surface structure and composition. Since reductive carbonization is a key step in the activation of iron-based catalysts, in this work, Fe3O4-O (expose the {111} crystal planes) with different particle size, and similar particle size but exposing different crystal planes, {111} and {110} (Fe3O4-RD), have been prepared to explore the effect of particle size and surface structure on the carbonization process. The results show that the 50 nm Fe3O4-O particles changed more significantly than the one with large particle size (2–10 μm) after carbonization. In situ XRD was used to monitor the phase change of Fe3O4 with exposing different surface planes during carbonization, the results show that 150 nm Fe3O4-O and Fe3O4-RD particles behave differently in carbonization rate and have different iron carbide concentration in the end, which indicates the carbonization process can be affected by exposed crystal planes. TEM analysis reveals that Fe3O4@FexC core-shell structure formed after carbonization.
A research paper
Influence of pretreatment conditions on the structure and catalytic performance of supported cobalt catalysts derived from metal-organic frameworks
SUN Jia-qiang, ZHENG Shen-ke, CHEN Jian-gang
 doi: 10.1016/S1872-5813(23)60352-4
Abstract(49) HTML(24) PDF 6612KB(6)
Supported cobalt catalysts (Co@C-ZnZrO2 and Co/ZnZrO2) were prepared through a metal-organic frameworks (MOFs)-mediated synthesis strategy. The influence of MOFs pyrolysis on the structure and Fischer-Tropsch synthesis performance of supported cobalt catalysts was investigated. The crystalline phase and microstructure of supported cobalt catalysts were characterized by powder X-ray diffraction (XRD), transmission electron microscopy (TEM), high-resolution TEM (HRTEM), N2 adsorption-desorption and X-ray photoelectron spectroscopy (XPS). The Co/ZnZrO2 showed the CO conversion of 18.1% and the C5 + selectivity of 77.4%, whereas the Co@C-ZnZrO2 exhibited the CO conversion of 8.5% and the C5 + selectivity of 35.2%. The excellent CO conversion for Co/ZnZrO2 was attributed to the more exposure of active Co sites. Meanwhile, the activity of Co sites on Co@C-ZnZrO2 catalyst was restricted by the carbon layer, suppressing the adsorption and activation of syngas on Co sites.
Review of catalytic systems for direct synthesis of dimethyl carbonate containing dehydrating agent
CHENG Qing-yan, ZHANG Shuai, GU Yun-han, WANG Zhuo, WANG Jin-tao, LI Li, WANG Yan-ji, WANG Huan, QIAO Jin-dong
 doi: 10.1016/S1872-5813(23)60376-7
Abstract(75) HTML(14) PDF 17528KB(15)
Dimethyl carbonate (DMC) is a widely used environment-friendly green chemical, and the direct synthesis of DMC by CO2 and CH3OH has been the focus of research on clean conversion of CO2 in recent years. The design of efficient and stable catalysts and reaction processes to promote the conversion of CO2 is the key to whether DMC direct synthesis can be industrialized. In this paper, the research progress of catalytic systems for the direct synthesis of DMC from CO2 and CH3OH is reviewed, the reaction mechanism of different types of catalysts is introduced, mainly including ionic liquid catalyst, alkali metal carbonate catalyst, transition metal oxide catalyst, etc., the dehydration principle of various dehydrating agents and the promotion effect of reaction are expounded, the advantages and disadvantages of different catalytic-dehydration systems are analyzed. It is predicted that the development of efficient and stable catalysts and membrane materials with strong permeability to water, and the construction and implementation of new dehydration processes will be the focus of future research.
Effect of metal promoters on catalytic performance of Co/AC for higher alcohols synthesis from syngas
GUO Lei, LIU Pei-gong, GONG Kun, QI Xing-zhen, LIN Tie-jun
 doi: 10.1016/S1872-5813(23)60368-8
Abstract(37) HTML(13) PDF 4085KB(5)
Shifting products of Fischer-Tropsch synthesis (FTS) from paraffins to value-added higher alcohols receives great attention but remains great challenge. Herein, metal oxides of Mn, Zn, La and Zr are investigated as promoters to tune the activity and product distributions of Co/AC catalyst for syngas conversion. It is found that these promoters show different promotion effect on CO dissociation rate, the formation of Co2C phase and the alcohols selectivity. The formed Co2C/Co0 constitutes the dual active site for higher alcohols synthesis. The strongest CO dissociation rate is observed for Zn-promoted Co/AC catalyst, resulting in the highest activity and space-time yield (STY) of alcohols. The Mn promoter is most conducive to the formation of Co2C, but slightly decreases the activity. The similar CO dissociation rate and CO conversion are obtained over both Zr- and La-promoted Co/AC catalysts, but the Zr-promoted Co/AC catalyst exhibits the highest alcohols selectivity due to the function balance between CO non-dissociative insertion and CO dissociation.
Experimental study of hydrogen production via the steam reforming of hydrogen-rich biomass pyrolysis gas under the catalysis of Ni/γ-Al2O3
WANG Ti-peng, HU Si-han, LIU Ji, HU Bin, SUN Huai-de, ZHANG Zhen-xi, LU Qiang
 doi: 10.19906/j.cnki.JFCT.2023046
Abstract(73) HTML(16) PDF 1409KB(9)
In this paper, the steam reforming reactions of the hydrogen-rich biomass pyrolysis gas and methane (CH4) were compared. The influence mechanism of hydrogen-rich biomass pyrolysis gas components on the reforming reaction of CH4 and other low hydrocarbons was discussed, and the catalytic effect of Ni/γ-Al2O3 catalyst was revealed. H2 could provide a reductive atmosphere to maintain the dynamic balance of the highly active Ni0 on the catalyst surface, so as to improve its catalytic activity. At the same time, biomass pyrolysis gas could inhibit the conversion of transition carbon to graphitic carbon, reducing the influence of carbon deposition on the catalytic activity of Ni/γ-Al2O3. In addition, the influence of operating conditions such as reaction temperature, the ratio of steam and carbon (S/C), as well as space velocity on the steam reforming reaction of hydrogen-rich pyrolysis gas was investigated. The increase of reaction temperature and S/C ratio effectively promoted the steam reforming of CH4 and inhibited the production of carbon deposition. With the increase of space velocity, the competitiveness of CH4 steam reforming reaction was weakened, whereas that of water gas shift reaction and CH4 dry reforming was increased. Hence, the transformation of CH4 was inhibited. This paper cound lay a foundation for the research on the mechanism of biomass pyrolysis gas steam reforming reaction and the development of high-efficiency catalysts.
Highly Efficient Co-Al2O3 catalysts for Oxidative Dehydrogenation of Ethylbenzene to Styrene with CO2
SI Zhi-wei, DAN Shao-peng, CHEN Shu-wei, PAN Da-hai, WANG Ying-xiong, YAN Xiao-liang, LI Rui-feng
 doi: 10.19906/j.cnki.JFCT.2023039
Abstract(77) HTML(42) PDF 3766KB(9)
nCo-Al2O3 catalysts with different Co contents (n=2, 5, 10, 15, 20%) were prepared by a sol-gel approach. The effect of Co content on the nCo-Al2O3 catalyst structure and performance in the oxidative dehydrogenation of ethylbenzene to styrene by CO2 was investigated. The results showed that the isolated Co2 + ions on the nCo-Al2O3 catalysts had a positive influence on the catalytic activity, where the isolated tetrahedral Co2 + species were considered as the active sites. Co contents on the Co-Al2O3 catalyst greatly affected the structure of Co species and the catalytic performance. The isolated tetrahedral Co2 + species are preferentially generated on the resultant nCo-Al2O3 catalyst when the content of Co (n) is less than 10 wt.%; as a result, an increase of Co content here leads to the formation of more isolated Co2 + sites and then improves the catalytic activity of nCo-Al2O3 in the dehydrogenation of ethylbenzene. When Co content exceeded 10%, crystalline Co3O4 particles were obtained on the formed catalyst, which resulted in the decline of the isolated Co2 + sites and catalytic activity. Among various nCo-Al2O3 catalysts, 10Co-Al2O3 exhibited the best catalytic performance, with 64.4% conversion rate for ethylbenzene and 99.3% selectivity for styrene at 550 ℃. This catalyst remained stable without obvious deactivation for 30 h of reaction, which suggests that the isolated Co2 + species as active sites presented excellent structural stability and excellent anti-coke deposition.
Research progress of Fischer-Tropsch synthesis reaction mechanism
SU Jun-chao, LIU Le, HAO Qing-lan, LIU Xing-chen, TENG Bo-tao
 doi: 10.19906/j.cnki.JFCT.2023034
Abstract(200) HTML(361) PDF 2796KB(106)
Synthesis gas (CO + H2) conversion into clean fuels and chemicals through Fischer-Tropsch synthesis (FTS) is an important way to clean utilization of coal and ensure China's energy security. Investigation of FTS reaction mechanism at the molecular level, including of activation of synthesis gas on catalyst surface, the chain growth via CnHx* and CnHxOy*, as well as the chain termination into alkanes, olefins, alcohols, and acids, is the key to regulate FTS products, the rational design and development of high-performance catalysts. It is also a hot and difficult point in catalysis science. To study FTS reaction mechanism, intermediate detection, modeling compound addition, steady-state kinetics based on reaction mechanism, steady-state isotope transient kinetic analysis (SSITKA), first-principles calculations, and reaction networks, etc. have been applied to reveal the mechanism of synthesis gas conversion. This paper systematically summarizes the research results of reaction mechanism over the past century, proposes a reasonable route map for FTS reaction, and gives a prospection of the research on FTS mechanism.
The application of DFT calculation in the study of iron-based catalyst Fischer-Tropsch synthesis reaction
HE Fu-gui, ZHANG Tong, LIANG Jie, LI Hai-peng, HE Yu-rong, GAO Xin-hua, ZHANG Jian-li, ZHAO Tian-sheng
 doi: 10.1016/S1872-5813(23)60366-4
Abstract(140) HTML(16) PDF 8673KB(31)
Fischer-Tropsch synthesis is the key technology of indirect coal liquefaction. Iron-based catalysts are commonly used FTS catalysts. Limited by the complexity of phase transition and the difficulty of in-situ characterization, density functional theory (DFT) has become a necessary means to study the adsorption and reaction of surface species on iron-based catalysts. Based on the surface chemical properties of iron-carbon compounds, this review discusses the formation conditions of different iron carbide phases and the adsorption properties of surface species. Then, the FTS elementary reactions involved in the current DFT calculation research are briefly described, and the mechanism research of chain initiation, chain growth, and chain termination under different mechanisms is summarized. Combined with the experimental research progress, the regulation mechanism of the addition of promoters on the structure and performance of iron-based catalysts was summarized. Finally, combined with some frontier research progress, the existing problems of iron-based catalysts are summarized, and the role of surface carbon in catalytic reactions and the different catalytic effects of various phases are prospected.
Research on mechanism and catalysts of CO2 electroreduction to formate
ZHAO Ping-ping, LIAN Hong-lei
 doi: 10.19906/j.cnki.JFCT.2023048
Abstract(62) HTML(21) PDF 13652KB(12)
This paper reviews the latest progress in the field of CO2 electrocatalytic reduction to formate in the past five years. The reaction mechanism of CO2 electroreduction to formate and the types of catalysts used in this process are introduced, including metal catalysts, atomic dispersion catalysts, metal oxide catalysts, carbon materials, and composite material catalysts. The main factors affecting product selectivity, catalytic activity and stability are analyzed in detail from the perspectives of catalyst, electrolyte, reaction atmosphere and electrolytic cell. In view of the current research status of carbon dioxide electroreduction to formate, it is proposed to innovate on nanomaterials and composites, explore the active site and reaction path with the help of in-situ characterization technology, and guide the design and synthesis of efficient catalysts, improve the electrochemical reactor module to improve the catalytic efficiency and other issues can be regarded as the future research focus and development direction.
Technological advances in the production of high value oxygen-containing chemicals from coal via dimethyl oxalate
ZHANG Hong-xu, LIU Guo-guo, YU Jia-feng, SUN Jian
 doi: 10.19906/j.cnki.JFCT.2023044
Abstract(62) HTML(22) PDF 28580KB(16)
China's energy structure is rich in coal and less in oil, and the development of efficient and clean utilization of coal resources is a key development direction in China. Coal can synthesize dimethyl oxalate (DMO) after carbonylation by synthesis gas, and further hydrogenation can obtain oxygen-containing chemicals with high added value: such as methyl glycolate (MG), ethylene glycol (EG), ethanol (EO), etc. Among them, MG can prepare degradable materials polyglycolic acid (PGA), EG can synthesize polyethylene glycol (PEG), and EO can synthesize ethyl acetate (EAC), which have wide application prospects. This paper focuses on DMO hydrogenation reactions, analyzes the research status of catalysts used in each hydrogenation process, focuses on the regulation of catalyst composition, catalytic mechanism and new catalyst preparation technology, analyzes the problems and challenges in the development of DMO hydrogenation catalysts, and points out the application bottlenecks and future development trends of hydrogenation products and downstream products.
A research paper
Research Progress on the Design of Zeolite-based Core-shell Structure Catalysts and Their Reaction Mechanism for Diesel Vehicle Exhaust deNOx
JIA Ling-feng, SHAO Yuan-kai, LI Zhen-guo, Ren Xiao-ning, LI Kai-xiang, LIU Ji-xing, LIU Jian
 doi: 10.19906/j.cnki.JFCT.2023016
Abstract(178) HTML(56) PDF 12434KB(32)
Nitrogen oxides (NOx) from diesel engine exhaust is one of the main sources of environmental pollution. zeolite-based NH3-SCR catalysts have extensively investigated and have shown great promise for the efficient reduction of NOx because of their excellent NH3-SCR performance, robust hydrothermal stability and outstanding N2 selectivity. However, with the increasingly stringent environmental regulations and the implementation of the requirement of “zero emission” of diesel engine exhaust, it is particularly important to develop zeolite-based catalysts with more excellent catalytic activity and anti-poisoning performance, especially core-shell structure catalyst. In this review, we mainly focus on the recent research progress of the core-shell structure zeolite-based catalysts for NH3-SCR reactions with three commonly used Beta, ZSM-5, and SSZ-13 zeolite as the cores, the reaction mechanism of resistance to hydrothermal aging, sulfur poisoning, hydrocarbon poisoning, and alkali metal poisoning, as well as the future development and application prospects of zeolite-based core-shell structure catalysts.
Progress of In2O3-based catalysts in Thermal Catalytic CO2 hydrogenation reaction
JIAO Chun-xue, MU Hong-mei, GAO Peng, YANG Xing, TIAN Hai-feng, ZHA Fei
 doi: 10.19906/j.cnki.JFCT.2022086
Abstract(2573) HTML(128) PDF 45012KB(28)
Catalytic hydrogenation of CO2 is considered to be one of the most practical ways to produce value-added chemicals and fuels. However, due to the extreme chemical inertness, the high C-C coupling barrier and the many competing reactions, it is of vital important to develop the efficient catalysts for achieving the activation and transformation of CO2 into a variety of chemical products. In recent years, indium oxide has aroused great interest in CO2 hydrogenation due to its abundant oxygen vacancies, high selectivity of methanol and high activity of CO2 conversion. In this paper, the structure of In2O3 and the catalytic performance of In2O3-supported or metal-doped composite catalysts for CO2 hydrogenation to methanol are reviewed. The effects of the proximity of In2O3 to different zeolites and the migration of elements on the products of CO2 hydrogenation to hydrocarbons are also discussed. Finally, the challenges and development directions of selective hydrogenation of CO2 over In2O3-based catalysts are summarized.
2023, 51(8): 1-8.  
Abstract(63) HTML(15) PDF 50599KB(31)
The reaction pathway of methane and catalyst stability under supercritical water
WANG Peng-cheng, ZHAO Xue, YU Jie
2023, 51(8): 1035-1046.   doi: 10.19906/j.cnki.JFCT.2023019
Abstract(166) HTML(164) PDF 1770KB(56)
In supercritical water (SCW) condition, the gasification of biomass to H2 or CH4 has been studied extensively and proves to be critical in realising the upgrading of carbonaceous fuels. Given the extreme conditions of water at high pressure and temperature, along with the complex structure of biomass, the development of such a process still remains a challenge. In order to realize the complete decomposition of biomass and a high yield of desired products, such as CH4 and H2 at relatively milder conditions, various catalysts were synthesized and practiced. Different metals (such as Cr, Ni, Zn, Ru and Rh) were incorporated into various supports, such as mineral compounds of Al2O3, SiO2, TiO2, ZrO2, MgO, Y2O3, CeO2, silica-alumina, zeolites and carbon based supports of carbon nanotube, activated carbon. As a result, the long term stability of catalys is critical in the gasification of carbonaceous fuel in supercritical water condition. Therefore, this work focused on the stability of various support materials and deactivation of active metal components in supercritical water conditions with the purpose of choosing robust catalysts. In supercritical water condition, the effect of catalyst on carbonaceous fuels cracking, methanation reaction and water gas shift reaction determines the gasification efficienty as a whole. Unfortunately, the mechanism of methanation reaction is still unclear. Therefore, the CH4 formation mechanism and the effect of catalyst on CH4 conversion are emphasized in this work.
Research on the migration and transformation mechanism of nitrogen during biomass pyrolysis
LU Qiang, ZHAO Wei, XIA Yuan-gu, LIU Ji, MENG Han-xian, GUO Xue-wen, HU Si-han, HU Bin
2023, 51(8): 1047-1059.   doi: 10.19906/j.cnki.JFCT.2023025
Abstract(185) HTML(65) PDF 2221KB(61)
Biomass can be converted into high-value nitrogen-containing chemicals and nitrogen-containing carbon materials by pyrolysis technique, which significantly increases the value of biomass and lowers the risk of environmental pollution by nitrogen-containing pollutants. Therefore, a good understanding of the migration and conversion mechanisms of nitrogen during pyrolysis is critical for the advancement of biomass pyrolysis technique. Herein, the forms and contents of nitrogen in biomass were first summarized. Afterward, the transformation process of nitrogen from biomass to pyrolysis products was discussed based on the distribution of nitrogen in the solid, liquid, and gaseous pyrolysis products. Finally, the effects of fuel properties, pretreatment methods and pyrolysis conditions on the migration and transformation of nitrogen were discussed carefully. In addition, an outlook for future research on nitrogen migration in biomass pyrolysis process was provided.
Investigation progress on the synergy between coal and biomass during co-gasification
QI Jian-zi, YAO Jin-gang, CHEN Guan-yi, YI Wei-ming, YAN Bei-bei, CHENG Zhan-jun, YAO Yan, LIU Jing, LIU Xiao-yang, BI Chen-jie
2023, 51(8): 1060-1072.   doi: 10.19906/j.cnki.JFCT.2023007
Abstract(369) HTML(61) PDF 14505KB(119)
Co-gasification of coal and biomass, as one of the means to achieve efficient and clean utilization of coal, has a positive contribution to achieving carbon neutrality and carbon peaking. Co-gasification not only helps to overcome a series of problems derived from coal gasification alone, reduces the emission of SOx, NOx and other harmful substances, and improves coal reactivity but also helps to overcome the problems of low energy density, poor gasification efficiency and high tar yield existing in biomass gasification alone. Based on this, the progress in the research of influencing factors and synergetic reaction mechanism is reviewed in this work. The effects of feedstock type and pretreatment method, process parameters and gasifier type on the co-gasification process are summarized, the catalytic synergistic mechanism in the co-gasification process of coal and biomass is systematically described, the synergistic mechanism of non-catalytic factors in the co-gasification process is briefly outlined, and new methods to study the co-gasification process are comprehensively discussed. The main concern of the co-gasification process is sorted out, and prospects are made for constructing the synergistic pathway with the help of the new in situ technique and revealing the reaction mechanism in coupling the chemical reaction system with the combination of density functional theory and gasification dynamics models.
Research progress in the growth mechanism of carbon nanotubes prepared by catalytic pyrolysis of waste plastics
LI Shu-jiang, XIAO Hao-yu, JIANG Hao, YAO Ding-ding, CHEN Ying-quan, WANG Xian-hua, YANG Hai-ping, CHEN Han-ping
2023, 51(8): 1073-1083.   doi: 10.19906/j.cnki.JFCT.2023041
Abstract(137) HTML(70) PDF 9060KB(64)
Catalytic pyrolysis technology can convert waste plastics into high-quality carbon nanotubes (CNTs), achieving the recycling and high-value utilization of waste plastics. However, the process of plastic catalytic pyrolysis is complex, with numerous influencing factors, and the growth mechanism of carbon nanotubes is unclear. Therefore, this article elaborates on the influence of plastic structure and pyrolysis process on the growth process and structural characteristics of carbon nanotubes from the perspectives of plastic type, temperature, catalyst, etc., and analyzes the nucleation and growth mechanism of carbon nanotubes. It is found that the type and temperature of volatile matter will affect the structure of CNTs, while the performance of the catalyst will affect the diameter and growth mode of carbon nanotubes. The force between the catalyst and CNTs depends on the type of catalyst, and the carbon diffusion intensity at the boundary of CNTs is influenced by reaction conditions, catalyst and carbon source types. The relative size between the two determines the specific process of CNTs nucleation and growth.This review provides theoretical reference for the understanding of the process of preparing carbon nanotubes from waste plastic pyrolysis and the development of waste plastic resource utilization technologies.
Experimental study on preparation of bio-oil by hydrothermal liquefaction of three kinds of lignin
YANG Tian-hua, LIU Zheng, LI Bing-shuo, ZHANG Hai-jun, WANG He-yi
2023, 51(8): 1084-1095.   doi: 10.1016/S1872-5813(23)60345-7
Abstract(129) HTML(97) PDF 1830KB(40)
Lignin is a natural and renewable resource with aromatic structure. It can be converted into bio-oil by hydrothermal liquefaction. Due to the complex structure of wood fiber, the structural characteristics and reactivity of different kinds of lignin are different. Therefore, three typical lignin (kraft lignin (KL), enzymatic hydrolysis lignin (EHL) and ethanol lignin (OL)) were selected as raw materials. Firstly, physical and chemical properties of the raw materials were analyzed. Secondly, effects of reaction conditions on characteristics of their hydrothermal liquefaction bio-oil were investigated. Among them, EHL and OL are guaiacyl units. OL has the highest content of carbon and hydrogen elements, and its higher heating value reaches 23.54 MJ/kg. The aromatic characteristics are more obvious, and the phenolic hydroxyl content is relatively high. KL is mainly syringyl unit with less methoxy and phenolic hydroxyl groups. The results of liquefaction experiment show that when the reaction temperature was 300 ℃, yield and energy recovery rate of lignin bio-oil were the highest. The bio-oil yield ranked in the order of OL>KL>EHL. H/C ratio of bio-oil was concentrated within 1.0-1.4. Chemical composition of the three bio-oils was different. OL bio-oil contains 9.14% aromatic hydrocarbons, EHL bio-oil contains 41.34% phenolic species, and KL bio-oil has a higher acid content.
Catalytic pyrolysis of lignin for production of mono-aromatic hydrocarbons over supported hierarchical zeolite
WANG Shao-qing, HAN Yu, YI Wei-ming, LI Zhi-he, WAN Zhen, JIAO Yan
2023, 51(8): 1096-1105.   doi: 10.19906/j.cnki.JFCT.2023009
Abstract(245) HTML(58) PDF 16942KB(83)
Mono-aromatic hydrocarbons (MAHs) are important basic raw materials for organic chemicals industry. Catalytic pyrolysis of lignin can produce MAHs. However, the complicated components of pyrolysis vapours can result in rapid coke deactivation of the catalyst and the lower yields of mono-aromatic hydrocarbons. The lignin pyrolysis vapours were upgraded to MAHs by Ni or Ga modified hierarchical zeolite (HZSM-5@Al-SBA-15). The distribution of catalytic pyrolysis products and the coke deposition behavior of catalysts were investigated in a fixed bed reactor. Results showed that the hierarchical zeolites had the developed pore structure, which could effectively improve the mass transfer and diffusion performance of lignin pyrolysis vapours. Moreover, the introduction of metal elements and mesoporous shell modulated the acidity distribution of the catalysts. Compared with the pure HZSM-5, the relative content of MAHs (78.63%), Ga/HS (77.15%) and Ni-Ga/HS (72.44%) were increased, and the content of poly-aromatic hydrocarbons was effectively inhibited. The content of CO2 in the gas products increased, indicating that the catalyst could promote the decarboxylation reaction. In addition, the content of coke deposition with supported hierarchical zeolite catalysts was significantly reduced, which were Ni/HS (7.79%), Ga/HS (6.37%) and Ni-Ga/HS (6.63%), respectively. This indicated that the introduction of metal components improved the anti-coke performance of the catalysts. Therefore, the supported hierarchical zeolite based on metal modification and pore optimization could upgrade the lignin pyrolysis vapours into high quality aromatic hydrocarbons. This study provides a basic reference for the high value utilization of lignin waste.
Effects of decoupled temperature and pressure on the hydrothermal process of lignin
YU Shi-jie, ZHAO Peng, LIU Mao-qing, GAO Yu, LI Qing-hai, ZHANG Yan-guo, ZHOU Hui
2023, 51(8): 1106-1113.   doi: 10.19906/j.cnki.JFCT.2023029
Abstract(98) HTML(54) PDF 1156KB(46)
This study investigated the effects of decoupled temperature and pressure on lignin during the hydrothermal process. The effect of hydrothermal treatment on the lignin structure was evaluated, and the effects of decoupling temperature and pressure on the liquid products of the lignin were assessed under decoupling conditions. The results showed that lignin was composed almost entirely of the G-type monomer of coniferyl alcohol. After hydrothermal treatment, C–O bonds such as β–O–4 ester bonds in lignin were broken. Methoxy and aliphatic structures linked to oxygen-containing structures were converted into aliphatic carbon skeletons. The liquid phase products were initially vanillin and 3-(4-hydroxy-3-methoxyphenyl)-1-propanol, which were subsequently converted to guaiacol mainly by inter-monomer conversion and cleavage of the β–O–4 bond of the terminal guaiacyl unit of lignin. The decoupled high pressure inhibited the production of lignin liquid products and decreased the selectivity of isoeugenol in the products. The results of this paper are expected to provide more fundamental knowledge and understanding for the optimization of hydrothermal conversion process conditions of lignin.
Comparative experiments on the catalytic pyrolysis of herb residue by K2CO3 and K2FeO4
WU Jiang-su, LI Yan-bing, YU Zhi-hao, LANG Lin, LIU Hua-cai, YIN Xiu-li, WU Chuang-zhi
2023, 51(8): 1114-1125.   doi: 10.19906/j.cnki.JFCT.2023011
Abstract(153) HTML(106) PDF 2247KB(36)
The effects of K2CO3 (PC) and K2FeO4 (PF) on the catalytic pyrolysis of herb residue were investigated by using a thermogravimetric analyser, online mass spectrometry and a fixed-bed reactor, using herb residue as the raw material and loaded with PF and PC catalysts respectively by impregnation. The results showed that both PC and PF lowered the pyrolysis reaction temperature of the herb, enhanced the water vapour reforming reaction and significantly increased the pyrolysis gas yield and H2 content. At 500 ℃, the catalyst promoted the production of H2 and increased the H2/CO ratio of the pyrolysis gas from 0 to 1.29 and 1.92, respectively; at 700 ℃, PC and PF can significantly reduce the liquid-phase yield and increase the H2/CO of the gas product, with PF being more effective, reducing the liquid-phase yield by 30.9% and increasing the H2/CO increased by 38.5%. However, PF will decompose and release oxygen during the pyrolysis process, which makes NO emissions increase.
Enhancement of the production of light aromatics from poplar wood by combined approach of wet torrefaction pretreatment and catalytic fast pyrolysis using metal modified hierarchical zeolite
CAI Wei, HUANG Ming, ZHU Liang, ZHENG Yu-bo, CAI Bo, MA Zhong-qing
2023, 51(8): 1126-1136.   doi: 10.19906/j.cnki.JFCT.2023004
Abstract(125) HTML(41) PDF 1305KB(50)
Light aromatics are extremely important building blocks in the chemical industry which can be produced from the catalytic fast pyrolysis (CFP) of biomass. In this work, wet torrefaction pretreatment (WTP) was employed to improve the quality of poplar wood (PW) in terms of the synergetic deoxygenation and demineralization. Then, metal-modified hierarchical HZSM-5 was prepared by the combined approach of NaOH desilication pretreatment and metal (Zn, Ga, and Fe) modification. At last, the CFP of torrefied PW was carried out by using the metal-modified hierarchical HZSM-5 as catalyst to produce light aromatics. Results showed that the deoxygenation and demineralization rates gradually increased with the increase of WTP temperature from 180 to 260 ℃, the maximum removal rates of oxygen, K, Mg, Ca, and Na were 47.96%, 90.99%, 86.65%, 66.09%, and 36.29%, respectively. NaOH desilication pretreatment and metal modification on HZSM-5 promoted the formation of light aromatics. The Zn-modified hierarchical HZSM-5 presented the highest yield of light aromatics. The yield of aromatics increased first with the raise of catalyst-to-torrefied PW ratio from 1:1 to 1∶3, then decreased slightly at the highest catalyst-to-torrefied PW ratio of 1∶5. At last, the operation parameter of WTP and CFP was optimized which the maximum yield of light aromatics was 7.83 × 107 p.a./mg at WTP temperature of 220 ℃, catalyst-to-biomass ratio of 3∶1, and CFP temperature of 850 ℃.
XRD characterization of structural evolution in low-middle rank coals
LI Xia, ZENG Fan-gui, WANG Wei, DONG Kui
2016, 44(7): 777-783.  
[Abstract](570) [FullText HTML](230) [PDF 2169KB](46)
通过对28个最大镜质组反射率0.30%-2.05%镜煤样品的X射线衍射(XRD) 分析, 获得XRD结构参数, 得到这些参数随反射率增大呈现的阶段性规律。在镜质组反射率小于1.0%阶段, LaLc急剧增加, d002迅速减小, 含氧官能团的脱落和脂肪长度支链化程度减小占主导; 在1.0%-1.6%阶段, La持续增加, d002先增加后减小, Lc先减小然后趋于平稳, 芳香体系脱氢和调整空间位阻同时进行; 在1.6%-2.0%阶段, d002持续减小, LcLa的增大, 煤结构演化以芳构化为主。XRD结构参数演化与第一、二次煤化作用跃变关系密切。
Structural analysis of functional group and mechanism investigation of caking property of coking coal
LI Xiang, QIN Zhi-hong, BU Liang-hui, YANG Zhuang, SHEN Chen-yang
2016, 44(4): 385-393.  
[Abstract](366) [FullText HTML](345) [PDF 1138KB](38)
以11种炼焦煤为研究对象,分别进行FT-IR和黏结指数G测试。采用PeakFit软件对FT-IR谱峰进行分峰拟合和定量计算,研究炼焦煤特征官能团含量与其黏结性间的关系。结果表明,煤黏结性大小与其FT-IR吸收峰密切相关,特别是3 000-2 800和3 700-3 000 cm-1两个吸收带;脂肪族结构是煤黏结性形成的主要决定因素,通常脂肪链越短或支链化程度越高,越有利于煤的黏结性形成;含-OH(或-NH)的氢键缔合结构可以与脂肪链协同作用,共同决定煤的黏结性能。不论煤分子有多大,只要是结构单元缩合度较小而作为桥键的脂肪链较多的结构形式,在热解过程中就会生成大量适度分子量、以结构单元为基元的液相物质。氢键是煤中主要的分子间作用形式,当若干形成氢键的官能团聚集缔合时,其相互作用会更强,甚至会形成类似超分子的结构;在形成胶质体阶段,这类氢键缔合的结构也会被打破,并形成以胶质体液相为主的物质。这些液相物质的存在,有利于胶质体的流动、黏连和固化成为半焦,从而最终获得优越的黏结性。
Effect of Na2O on mineral transformation of coal ash under high temperature gasification condition
CHEN Xiao-dong, KONG Ling-xue, BAI Jin, BAI Zong-qing, LI Wen
2016, 44(3): 263-272.  
[Abstract](249) [FullText HTML](216) [PDF 1275KB](25)
利用XRD和FT-IR考察了高温弱还原气氛下Na2O对两种硅铝含量不同的煤灰中矿物质组成的影响, 揭示了Na2O影响煤灰熔融特性的本质.通过FactSage计算了高温下矿物质反应的ΔG, 探讨了Na2O影响煤灰中矿物质组成的机理.结果表明, Na2O对煤灰矿物质组成的影响与原煤灰的硅铝含量密切相关.硅铝总含量82.89%的煤灰, Na2O含量为5%-20%时, 钠长石和霞石的生成是煤灰熔融温度降低的主要原因; 当Na2O含量大于20%时, 导致煤灰熔融温度降低的原因是霞石的生成.硅铝总含量47.85%的煤灰, Na2O含量小于10%时, 没有含钠矿物质生成; 当Na2O含量大于10%时, 主要生成菱硅钙钠石、青金石和含钠的硅铝酸盐矿物, 导致煤灰熔融温度降低.FactSage计算表明生成含Na矿物质反应的ΔG较小, 其在高温下更容易发生.
High resolution TEM image analysis of coals with different metamorphic degrees
LI Xia, ZENG Fan-gui, SI Jia-kang, WANG Wei, DONG Kui, CHENG Li-yuan
2016, 44(3): 279-286.  
[Abstract](365) [FullText HTML](290) [PDF 12189KB](29)
利用高分辨率透射电子显微镜(HRTEM) 分析了三种不同变质程度煤样的结构特征.基于傅里叶-反傅里叶变换方法, 并结合Matlab、Arcgis和AutoCAD软件, 通过图像分析技术, 获得了HRTEM照片的晶格条纹参数.结果表明, 三种煤样的晶格条纹呈现不同特征, 按条纹长度分别归属于1×1-8×8共计八个类型.以3×3为临界点, 在1×1和2×2中, ML-8中芳香层片的比例高于DP-4和XM-3;在3×3-8×8中, ML-8中芳香层片的比例低于DP-4和XM-3.对比HRTEM和XRD参数d002发现, 随着镜质组反射率的增加d002都呈现递减趋势.
Research progress in the direct conversion of syngas to lower olefins
YU Fei, LI Zheng-jia, AN Yun-lei, GAO Peng, ZHONG Liang-shu, SUN Yu-han
2016, 44(7): 801-814.  
[Abstract](903) [FullText HTML](476) [PDF 8665KB](78)
合成气直接催化转化制备低碳烯烃是C1化学与化工领域中一个极具挑战性的研究课题, 具有流程短、能耗低等优势, 已成为非石油路径生产烯烃的新途径。直接转化方式主要包括经由OX-ZEO双功能催化剂直接制低碳烯烃的双功能催化路线以及经由费托反应直接制备低碳烯烃的FTO路线。综述简述了近年来在合成气直接制备低碳烯烃方面的研究进展, 重点讨论了低碳烯烃的形成机理、新型催化剂的研发及助剂对其催化性能的影响, 并对合成气直接制烯烃的未来进行了展望。
Relationship between coal ash fusibility and ash composition in terms of mineral changes
WANG Yang, LI Hui, WANG Dong-xu, DONG Chang-qing, LU Qiang, LI Wen-yan
2016, 44(9): 1034-1042.  
[Abstract](379) [FullText HTML](220) [PDF 809KB](38)
通过在一种真实煤灰中添加不同的氧化物或直接用氧化物配制合成灰,探究了不同灰成分对灰熔融特性的影响规律。利用FactSage 7.0对不同灰分的熔融过程进行了热力学模拟,通过熔融过程中的矿物质变化为各种灰成分对熔融特性的影响规律提供理论依据。结果表明,氧化钠对灰熔点的降低作用源于钠长石和霞石对钙长石的取代;氧化镁含量的增加对灰熔点起先降低后升高的作用,当氧化镁含量超过一定时,产生的镁橄榄石能够升高灰熔点;硫对灰熔点的升高作用源于镁橄榄石和硫酸钙对透辉石的取代;氧化钙含量的增加对灰熔点起到先降低后升高的作用,当氧化钙含量超过一定时,硅从熔点较低的矿物质迁移到熔点较高的矿物质中,升高了灰熔点。在与硅氧单元体结合的过程中,氧化钠优先于氧化钙;与氧化钙和硅氧单元体结合的氧化物的优先级为:氧化铝>氧化镁>氧化铁。
Performance of Mn-Ce catalysts supported on different zeolites in the NH3-SCR of NOx
HUANG Zeng-bin, LI Cui-qing, WANG Zhen, XU Sheng-mei, FENG Ling-bo, WANG Hong, SONG Yong-ji, ZHANG Wei
2016, 44(11): 1388-1393.  
[Abstract](356) [FullText HTML](229) [PDF 780KB](28)
Effect of rare-earth element modification on the performance of Cu/ZnAl catalysts derived from hydrotalcite precursor in methanol steam reforming
YANG Shu-qian, HE Jian-ping, ZHANG Na, SUI Xiao-wei, ZHANG Lei, YANG Zhan-xu
2018, 46(2): 179-188.  
[Abstract](307) [FullText HTML](155) [PDF 7028KB](26)
采用原位合成法在γ-Al2O3表面合成了锌铝水滑石,再通过顺次浸渍法制备了一系列掺杂稀土改性的MM=Y、La、Ce、Sm、Gd)/Cu/ZnAl催化材料,并将其应用于甲醇水蒸气重整制氢反应。探讨了稀土掺杂改性对Cu/ZnAl催化剂催化性能的影响,并采用XRD、SEM-EDS、BET、H2-TPR、XPS和N2O滴定等手段对催化剂进行了表征。结果表明,催化剂的活性与Cu比表面积和催化剂的还原性质密切相关,Cu比表面积越大,还原温度越低,催化活性越高。稀土Ce、Sm、Gd的引入能改善活性组分Cu的分散度、Cu比表面积以及催化剂的还原性质,进而提高催化剂的催化活性。其中,Ce/Cu/ZnAl催化剂表现出最佳的催化活性,在反应温度为250 ℃时,甲醇转化率达到100%,CO含量为0.39%,相比Cu/ZnAl催化剂,甲醇转化率提高了近40%。
Effects of NH3 and SO3 on the generation of ammonium bisulfate and ammonium sulfate
YANG Jian-guo, YANG Wei-ying, ZHENG Fang-dong, ZHAO Hong
2018, 46(1): 92-98.  
[Abstract](246) [FullText HTML](169) [PDF 865KB](26)
Research progress on emission and control technologies of arsenic, selenium and lead in coal-fired power plants
HUANG Yong-da, HU Hong-yun, GONG Hong-yu, LIU Hui-min, FU Biao, LI Shuai, LUO Guang-qian, YAO Hong
2020, 48(11): 1281-1297.  
[Abstract](394) [FullText HTML](110) [PDF 8248KB](39)
Preparation of core-shell catalysts for one-step synthesis of dimethyl ether from syngas
WANG Wen-li, WANG Yan, CHEN Yue-xian, ZHAO Wen-chao, LI Rui-feng
2013, 41(08): 1003-1009.  
[Abstract](2302) [PDF 13334KB](49)
A core-shell catalyst CuO-ZnO-Al2O3@Al2O3 for one-step synthesis of dimethyl ether from synthesis gas was prepared using glucose, sucrose or starch as template, and characterized by scanning electron microscopy (SEM) with energy dispersive spectroscopy (EDS). The thickness of the Al2O3 shell in the catalyst was altered by controlling the synthesis condition, such as temperature and time. The catalytic performance of dimethyl ether (DME) synthesized from CO hydrogenation on the catalysts were investigated. The conversion of CO and the selectivity of DME on CuO-ZnO-Al2O3@Al2O3 achieved 35.2% and 61.1% at 260 ℃, 5.0 MPa and 1 500 mL/(h·gcat), respectively.
Effect of wastewater treatment processes on thermal treatment properties of sewage sludge
JIE Li-Beng, Zheng-Shi-Mei, LI Chao
2009, 37(04): 501-505.  
[Abstract](1673) [PDF 1335KB](49)
The properties of pyrolysis and combustion for five different sewage sludges are studied by thermal gravimetric analysis at a heating rate of 10℃/min in the atomosphere of nitrogen and oxygen, respectively. The results show that both of the “anaerobic” wastewater treatment and the sludge anaerobic digestion make the organic compounds in sludge so complicated that the organic compounds decomposition and release temperature becomes higher during pyrolyzing, and the “aerobic + anaerobic” process makes the organic compounds in sludge more complicated than the “anaerobic +aerobic” process. There is no influence on the combustion process and the burnout point, but can make the combustion temperature of sludge higher. The thermal reaction mechanisms have been studied with šatava-šesták equation. It shows that the pyrolysis mechanism of these sludges is a process of volatile diffusion at first and then the chemical reaction function, while the combustion mechanism of them is a process of chemical reaction and diffusion function.