Supervisor：Chinese Academy of Sciences
Sponsors by：
Shanxi Institute of Coal Chemistry, Chinese Academy of Sciences Chinese Chemical Society
Editor-in-Chief：Fang yi tian
Email：rlhx@sxicc.ac.cn
ISSN 0253-2409(印刷版)
1872-5813(网络版)
CN 14-1140/TQ
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).
Preparation of CoSOH/Co(OH)2 Composite Nanosheets and Its Catalytic Performance for Oxygen Evolution
, Available online ,
doi: 10.1016/S1872-5813(21)60077-4
Abstract:
2021, 49(8): 1057-1076.
doi: 10.1016/S1872-5813(21)60093-2
Abstract:
Waste gasification has the potential to contribute to China’s transition towards carbon neutrality and zero waste cities via the recirculation of waste as secondary carbon feedstock for the production of chemicals with lower/and or zero carbon footprint, green hydrogen with zero carbon footprint and CO2-neutral synthetic liquid fuels. With China’s significant coal gasification capacity and associated experiences and expertise, Coal-to-X could act as a bridge to Waste-to-X for carbon intensive sectors such as the waste management, chemical production and mobility sectors. To illustrate the opportunities in these areas, this article presented highlights from dynamic global developments in waste gasification, focusing on pioneering industrial developments in Germany between 1980−2000’s as well as current international developments. Lessons learnt from previous and current waste gasification project deployment are shared and enabled the identification of problems which will have to be addressed in the transition from coal gasification towards mono-waste gasification technologies. Additionally, a qualitative evaluation of gasification technologies pointed to the strengths and weaknesses of fixed-bed, fluidized-bed and entrained-flow gasification principles in their application for waste gasification.
Waste gasification has the potential to contribute to China’s transition towards carbon neutrality and zero waste cities via the recirculation of waste as secondary carbon feedstock for the production of chemicals with lower/and or zero carbon footprint, green hydrogen with zero carbon footprint and CO2-neutral synthetic liquid fuels. With China’s significant coal gasification capacity and associated experiences and expertise, Coal-to-X could act as a bridge to Waste-to-X for carbon intensive sectors such as the waste management, chemical production and mobility sectors. To illustrate the opportunities in these areas, this article presented highlights from dynamic global developments in waste gasification, focusing on pioneering industrial developments in Germany between 1980−2000’s as well as current international developments. Lessons learnt from previous and current waste gasification project deployment are shared and enabled the identification of problems which will have to be addressed in the transition from coal gasification towards mono-waste gasification technologies. Additionally, a qualitative evaluation of gasification technologies pointed to the strengths and weaknesses of fixed-bed, fluidized-bed and entrained-flow gasification principles in their application for waste gasification.
2021, 49(8): 1077-1085.
doi: 10.19906/j.cnki.JFCT.2021048
Abstract:
During the direct coal liquefaction process, coal direct liquefaction residue (CDLR), which accounts for about 30% of the coal input, will be produced and the polycyclic aromatic hydrocarbons can be extracted from it by extraction to prepare high-value carbon materials. The influences of composition and structure of extractants on the extraction rate and properties of extracted products were systematically summarized. The extraction rate of the extractants which have aromatic structure or nitrogen and oxygen atom can reach more than 50%. The extracts in alkane organic solvents mainly contain condensed aromatic structure with 2–4 benzene rings and have a lower molecular weight and heteroatom content. The extracts in heteroatoms containing solvents are mainly composed of condensed aromatic structure with 4–7 benzene rings and have a larger molecular weight. And they are rich in heteroatoms, such as nitrogen, oxygen and sulfur, and have a high atomic ratio of C/H. The extracts of pyridinium-based ionic liquids have higher atomic ratio of C/H and aromaticity. And the ash content of the extracts of ionic liquids containing organic acid ions is close to 0. When coal liquefaction oil or coal tar distillate are used as extractants, the extraction rate can reach 60%, which are suggested for industrial applications of CDLR extraction.
During the direct coal liquefaction process, coal direct liquefaction residue (CDLR), which accounts for about 30% of the coal input, will be produced and the polycyclic aromatic hydrocarbons can be extracted from it by extraction to prepare high-value carbon materials. The influences of composition and structure of extractants on the extraction rate and properties of extracted products were systematically summarized. The extraction rate of the extractants which have aromatic structure or nitrogen and oxygen atom can reach more than 50%. The extracts in alkane organic solvents mainly contain condensed aromatic structure with 2–4 benzene rings and have a lower molecular weight and heteroatom content. The extracts in heteroatoms containing solvents are mainly composed of condensed aromatic structure with 4–7 benzene rings and have a larger molecular weight. And they are rich in heteroatoms, such as nitrogen, oxygen and sulfur, and have a high atomic ratio of C/H. The extracts of pyridinium-based ionic liquids have higher atomic ratio of C/H and aromaticity. And the ash content of the extracts of ionic liquids containing organic acid ions is close to 0. When coal liquefaction oil or coal tar distillate are used as extractants, the extraction rate can reach 60%, which are suggested for industrial applications of CDLR extraction.
2021, 49(8): 1086-1094.
doi: 10.1016/S1872-5813(21)60074-9
Abstract:
Pyrolysis is an effective way for clean and efficient use of coal, as well as an important way for the efficient conversion of waste plastics. Polyvinyl chloride (PVC) and Pingshuo (PS) coal were used in this research object. A two-step treatment scheme was proposed for chlorine-containing plastics that are difficult to be treated harmlessly. The PVC was preheated to remove most of the chlorine, and then the pretreated PVC residue (DPVC) and coal were co-pyrolyzed. GC, simulated distillation, GC-MS, elemental analysis, FT-IR and Raman spectroscopy were used to analyze and characterize the composition and properties of pyrolysis gas, tar and char. The results showed that the co-pyrolysis process of DPVC and PS coal has a synergistic effect, and the co-pyrolysis has an obvious positive synergistic effect on the formation of char and tar. The experimental value of tar yield is higher than theoretical calculation and the maximum increasing value is 3.35%. There is a negative synergistic effect on the formation of pyrolysis water and gas, in which CH4 has the largest decrease in yield, meaning the strongest negative synergy. Co-pyrolysis increases the content of light tar, significantly increases the content of naphthalenes, and reduces the asphalt. When the DPVC addition was 10%, the content of light tar increases by 5 percentage points over the theoretical calculation value. In addition, the co-pyrolysis char surface is smoother, the structure becomes more orderly, and the graphitization degree increases.
Pyrolysis is an effective way for clean and efficient use of coal, as well as an important way for the efficient conversion of waste plastics. Polyvinyl chloride (PVC) and Pingshuo (PS) coal were used in this research object. A two-step treatment scheme was proposed for chlorine-containing plastics that are difficult to be treated harmlessly. The PVC was preheated to remove most of the chlorine, and then the pretreated PVC residue (DPVC) and coal were co-pyrolyzed. GC, simulated distillation, GC-MS, elemental analysis, FT-IR and Raman spectroscopy were used to analyze and characterize the composition and properties of pyrolysis gas, tar and char. The results showed that the co-pyrolysis process of DPVC and PS coal has a synergistic effect, and the co-pyrolysis has an obvious positive synergistic effect on the formation of char and tar. The experimental value of tar yield is higher than theoretical calculation and the maximum increasing value is 3.35%. There is a negative synergistic effect on the formation of pyrolysis water and gas, in which CH4 has the largest decrease in yield, meaning the strongest negative synergy. Co-pyrolysis increases the content of light tar, significantly increases the content of naphthalenes, and reduces the asphalt. When the DPVC addition was 10%, the content of light tar increases by 5 percentage points over the theoretical calculation value. In addition, the co-pyrolysis char surface is smoother, the structure becomes more orderly, and the graphitization degree increases.
2021, 49(8): 1095-1101.
doi: 10.1016/S1872-5813(21)60081-6
Abstract:
In order to study the performance of DCLR (direct coal liquefaction residue) modified asphalt mortar, different DCLR modified asphalt mortar with different DCLR contents and filler-asphalt ratios (FA) was prepared. The high-and-low temperature and fatigue performance of asphalt mortar was analyzed by a dynamic shear rheometer and a bending beam rheometer. Using the variance analysis method the influence of the single factor (temperature, DCLR content, FA) and the coupling between these factors on the performance of asphalt mortar was investigated. The results show that the addition of DCLR and filler can significantly improve the high-temperature performance of asphalt mortar, but damage the low-temperature performance and the fatigue performance of asphalt mortar. To comprehensively balance the effects of DCLR content and FA on the performance of the mortar, the DCLR content of 10% and the FA of 1.0 are recommended. Besides, the single factor (temperature, DCLR content, FA) and the coupling between these factors have significant effects on the performance of asphalt mortar, but the effect of the coupling is smaller than that of the single factor.
In order to study the performance of DCLR (direct coal liquefaction residue) modified asphalt mortar, different DCLR modified asphalt mortar with different DCLR contents and filler-asphalt ratios (FA) was prepared. The high-and-low temperature and fatigue performance of asphalt mortar was analyzed by a dynamic shear rheometer and a bending beam rheometer. Using the variance analysis method the influence of the single factor (temperature, DCLR content, FA) and the coupling between these factors on the performance of asphalt mortar was investigated. The results show that the addition of DCLR and filler can significantly improve the high-temperature performance of asphalt mortar, but damage the low-temperature performance and the fatigue performance of asphalt mortar. To comprehensively balance the effects of DCLR content and FA on the performance of the mortar, the DCLR content of 10% and the FA of 1.0 are recommended. Besides, the single factor (temperature, DCLR content, FA) and the coupling between these factors have significant effects on the performance of asphalt mortar, but the effect of the coupling is smaller than that of the single factor.
2021, 49(8): 1102-1110.
doi: 10.19906/j.cnki.JFCT.2021051
Abstract:
8 kinds of mixed oil with different feeding time in the same coking cycle were the objects of the study. The optical structure, morphology structure and microcrystalline structure of needle coke formed by mixed oil with different feeding time in coking cycle were quantitatively analyzed by means of polarizing microscope, scanning electron microscope (SEM), XRD and Raman spectroscopy. The results show that the yield of coke after the thermal conversion of the mixed oil is higher than the theoretically calculated yield, indicating that the heavy oil participates in the thermal conversion reaction to form the coke with a streamlined optical structure. In the optical structure of calcined needle coke, MO-8" has the highest fiber content, followed by MO-16", and MO-32" has the lowest fiber content. SEM further proves that MO-8" has more lamellar number and more regular orientation. XRD analysis of needle coke confirms that the microcrystalline structure parameters (interlayer spacing d002, lamellar content N and the number of carbon atoms in each layer n) are very close. However, there are obvious differences in the content of graphite microcrystalline (Ig), and among which MO-8" has the highest content, followed by MO-4", and sample MO-32" has the lowest content. Furthermore Raman spectral analysis certifies that the basic microstructure of needle coke is similar. The fundamental reason is that the refined coal-tar pitch in the mixed oil determines the basic microstructure of needle coke. Due to the continuous circulation of heavy oil in the system, the microstructure of needle coke are different. Hence, the coking cycle is not easy to exceed 32 h in coal-based needle coke production, or else it will seriously affect the microstructure of needle coke.
8 kinds of mixed oil with different feeding time in the same coking cycle were the objects of the study. The optical structure, morphology structure and microcrystalline structure of needle coke formed by mixed oil with different feeding time in coking cycle were quantitatively analyzed by means of polarizing microscope, scanning electron microscope (SEM), XRD and Raman spectroscopy. The results show that the yield of coke after the thermal conversion of the mixed oil is higher than the theoretically calculated yield, indicating that the heavy oil participates in the thermal conversion reaction to form the coke with a streamlined optical structure. In the optical structure of calcined needle coke, MO-8" has the highest fiber content, followed by MO-16", and MO-32" has the lowest fiber content. SEM further proves that MO-8" has more lamellar number and more regular orientation. XRD analysis of needle coke confirms that the microcrystalline structure parameters (interlayer spacing d002, lamellar content N and the number of carbon atoms in each layer n) are very close. However, there are obvious differences in the content of graphite microcrystalline (Ig), and among which MO-8" has the highest content, followed by MO-4", and sample MO-32" has the lowest content. Furthermore Raman spectral analysis certifies that the basic microstructure of needle coke is similar. The fundamental reason is that the refined coal-tar pitch in the mixed oil determines the basic microstructure of needle coke. Due to the continuous circulation of heavy oil in the system, the microstructure of needle coke are different. Hence, the coking cycle is not easy to exceed 32 h in coal-based needle coke production, or else it will seriously affect the microstructure of needle coke.
2021, 49(8): 1111-1121.
doi: 10.1016/S1872-5813(21)60064-6
Abstract:
The effects of steaming at varying times and temperatures on ZSM-5 pore structures, framework Al distribution, acid properties and ethanol to propene (ETP) catalytic performance were systematically studied in this study. The results show that the crystallinity and specific surface areas of steam treated ZSM-5 samples decrease with the increase treatment time and temperature. 27Al MAS NMR and Co(Ⅱ) exchange-ICP results show that the isolated framework Al species (Alsingle) can be preferentially removed from the zeolite framework, while the paired Al sites (Alpairs) remain relatively stable after steam treatment. The characterization of Py-IR reveals that the concentration of B acid sites and the acid strength are all declined with the steaming time or temperature increase. The catalytic results of ETP at 450 ℃ show that the sample after steaming gives improved selectivities to propene and butene at the expense of ethene conversion and alkanes selectivity relative to the unmodified zeolite. Besides, a good positive correlation between ethylene conversion and Alsingle concentration is found, whereas the propene formation is influenced by the combination effect of Alsingle and Alpairs sites.
The effects of steaming at varying times and temperatures on ZSM-5 pore structures, framework Al distribution, acid properties and ethanol to propene (ETP) catalytic performance were systematically studied in this study. The results show that the crystallinity and specific surface areas of steam treated ZSM-5 samples decrease with the increase treatment time and temperature. 27Al MAS NMR and Co(Ⅱ) exchange-ICP results show that the isolated framework Al species (Alsingle) can be preferentially removed from the zeolite framework, while the paired Al sites (Alpairs) remain relatively stable after steam treatment. The characterization of Py-IR reveals that the concentration of B acid sites and the acid strength are all declined with the steaming time or temperature increase. The catalytic results of ETP at 450 ℃ show that the sample after steaming gives improved selectivities to propene and butene at the expense of ethene conversion and alkanes selectivity relative to the unmodified zeolite. Besides, a good positive correlation between ethylene conversion and Alsingle concentration is found, whereas the propene formation is influenced by the combination effect of Alsingle and Alpairs sites.
2021, 49(8): 1122-1131.
doi: 10.1016/S1872-5813(21)60124-X
Abstract:
The reaction mechanism of the isomerization of glucose to fructose and further dehydration of fructose to 5-hydroxymethylfurfural (5-HMF) in subcritical water was investigated by the dispersion-corrected density functional theory (DFT-D) method with Dmol3 package in Materials Studio. The implicit solvent model was used to evaluate the bulk solvation under the conductor-like screening model (COSMO) approach, in which a dielectric constant ( ε ) of 27 was used to represent the subcritical water at 523.15 K. The explicit solvent model was adopted with a hybrid micro-solvation-continuum approach, to indicate the micro-solvation by explicit H2O molecules and the bulk solvation with ε = 27. The calculation results indicate that explicit H2O molecules participate in the reaction and catalytically promote the proton transfer processes, suggesting that the explicit solvent model is preferable to the implicit solvent model to represent the conversion of 5-HMF in subcritical water. The isomerization of glucose to fructose is exothermic by 5.26 kcal/mol, where the isomerization of open-chain glucose to enol form is the rate-determining step, with the activation energy of 33.89 kcal/mol; the free energy of transition state configuration depends upon both the difficulty in α–H extraction of open-chain glucose and the stability of formed carbocation. In contrast, the hydration of fructose to 5-HMF is exothermic by 12.93 kcal/mol and the first hydration is the rate-determining step, with the activation energy of 50.59 kcal/mol; the free energy of transition state configuration is determined by the stability of carbocation formed by the dehydration of protonated OH group at C(2) site of fructose. This work discloses the promoting effect of Brønsted base on the isomerization of glucose to fructose and that of Brønsted acid on the dehydration of fructose to 5-HMF, which may provide certain clues to the modification of catalytic sites and the selection of solvent in the conversion of glucose to 5-HMF.
The reaction mechanism of the isomerization of glucose to fructose and further dehydration of fructose to 5-hydroxymethylfurfural (5-HMF) in subcritical water was investigated by the dispersion-corrected density functional theory (DFT-D) method with Dmol3 package in Materials Studio. The implicit solvent model was used to evaluate the bulk solvation under the conductor-like screening model (COSMO) approach, in which a dielectric constant ( ε ) of 27 was used to represent the subcritical water at 523.15 K. The explicit solvent model was adopted with a hybrid micro-solvation-continuum approach, to indicate the micro-solvation by explicit H2O molecules and the bulk solvation with ε = 27. The calculation results indicate that explicit H2O molecules participate in the reaction and catalytically promote the proton transfer processes, suggesting that the explicit solvent model is preferable to the implicit solvent model to represent the conversion of 5-HMF in subcritical water. The isomerization of glucose to fructose is exothermic by 5.26 kcal/mol, where the isomerization of open-chain glucose to enol form is the rate-determining step, with the activation energy of 33.89 kcal/mol; the free energy of transition state configuration depends upon both the difficulty in α–H extraction of open-chain glucose and the stability of formed carbocation. In contrast, the hydration of fructose to 5-HMF is exothermic by 12.93 kcal/mol and the first hydration is the rate-determining step, with the activation energy of 50.59 kcal/mol; the free energy of transition state configuration is determined by the stability of carbocation formed by the dehydration of protonated OH group at C(2) site of fructose. This work discloses the promoting effect of Brønsted base on the isomerization of glucose to fructose and that of Brønsted acid on the dehydration of fructose to 5-HMF, which may provide certain clues to the modification of catalytic sites and the selection of solvent in the conversion of glucose to 5-HMF.
2021, 49(8): 1132-1139.
doi: 10.1016/S1872-5813(21)60057-9
Abstract:
Highly selective synthesis of liquefied petroleum gas (LPG,${\rm{C}}_3^0 $ and ${\rm{C}}_4^0 $ ) from CO2 hydrogenation have realized over the In2O3/SSZ-13 bifunctional catalyst. The physicochemical properties of the bifunctional catalyst were characterized by X-ray diffraction spectroscopy (XRD), N2 physical adsorption, scanning electron microscopy (SEM), transmission electron microscopy (TEM) and NH3 temperature-programmed desorption (NH3-TPD). The particle size effect of In2O3 and reaction conditions were investigated for CO2 hydrogenation to LPG over the In2O3/SSZ-13 bifunctional catalyst. Results indicate that CO2 conversion and CO selectivity are related to the particle size of In2O3, and fresh 5 nm In2O3 shows the highest CO2 conversion (11.7%) and the highest CO selectivity (61.0%), since it is more prone to reverse water gas reaction (RWGS). However, the hydrocarbon distribution does not exhibit a dependence of In2O3 size changes, and the selectivity of LPG maintains at 90% and the selectivity of propane reaches up to 76.8% due to the 8-MR micropores and strong acid sites of SSZ-13 zeolite. Additionally, the yield of LPG shows a volcano type with increasing reaction temperature, and the optimal reaction temperature is 370 ℃. Low space velocity is more favorable to the CO2 conversion, and LPG selectivity in hydrocarbon products still maintains about 90%. High reaction pressure is beneficial to improving the yield of LPG via promoting the secondary hydrogenation reaction over the SSZ-13 zeolite and inhibiting CO formation. Furthermore, no obvious deactivation is observed after a time on stream (TOS) of 100 h over the In2O3/SSZ-13 bifunctional catalyst at 350 ℃, 3 MPa and 9000 mL/(gcat·h). The research provides a new strategy for highly selective synthesis of LPG from CO2 hydrogenation.
Highly selective synthesis of liquefied petroleum gas (LPG,
2021, 49(8): 1140-1147.
doi: 10.19906/j.cnki.JFCT.2021050
Abstract:
High thermal conductivity supports, core-shell structure SiO2@Al, was successfully prepared by hydrolyzing tetraethyl orthosilicate (TEOS) under weak alkaline condition and using hexadecyl trimethyl ammonium bromide (CTAB) as the template. 15% (mass fraction) of cobalt was loaded on these supports by excessive impregnation method for Fischer-Tropsch synthesis reaction. The prepared catalysts have high metal aluminum content, high specific surface shell layer and relatively uniform pore size of 2.6−2.8 nm. By changing the added amount of TEOS, the content of silica in the supports and the thickness of the shell layer can be adjusted. As the thickness of the silica shell layer increases, the specific surface area of the supports gradually increases, the interaction between cobalt and the supports increases, and at the same time, the reduction degree of the catalysts decreases. The silica shell enhances the dispersion of metallic cobalt and avoids deactivation caused by agglomeration of metallic cobalt on aluminum particles. Under the condition of similar conversion rate, the catalyst 15Co/5-SiO2@Al with a thinner shell layer has the best performance in Fischer-Tropsch synthesis which is mainly due to the moderate metal-support interaction between the thin silica shell layer and metal cobalt particles. The thinner silica shell layer can anchor and disperse cobalt species to increase the reduction degree of cobalt species.
High thermal conductivity supports, core-shell structure SiO2@Al, was successfully prepared by hydrolyzing tetraethyl orthosilicate (TEOS) under weak alkaline condition and using hexadecyl trimethyl ammonium bromide (CTAB) as the template. 15% (mass fraction) of cobalt was loaded on these supports by excessive impregnation method for Fischer-Tropsch synthesis reaction. The prepared catalysts have high metal aluminum content, high specific surface shell layer and relatively uniform pore size of 2.6−2.8 nm. By changing the added amount of TEOS, the content of silica in the supports and the thickness of the shell layer can be adjusted. As the thickness of the silica shell layer increases, the specific surface area of the supports gradually increases, the interaction between cobalt and the supports increases, and at the same time, the reduction degree of the catalysts decreases. The silica shell enhances the dispersion of metallic cobalt and avoids deactivation caused by agglomeration of metallic cobalt on aluminum particles. Under the condition of similar conversion rate, the catalyst 15Co/5-SiO2@Al with a thinner shell layer has the best performance in Fischer-Tropsch synthesis which is mainly due to the moderate metal-support interaction between the thin silica shell layer and metal cobalt particles. The thinner silica shell layer can anchor and disperse cobalt species to increase the reduction degree of cobalt species.
2016, 44(7): 777-783.
摘要：
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, La和Lc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, Lc和La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。
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, La和Lc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, Lc和La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。
2016, 44(4): 385-393.
摘要：
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。
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。
2016, 44(3): 263-272.
摘要：
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.
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.
2016, 44(7): 801-814.
摘要：
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。
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。
2016, 44(11): 1388-1393.
摘要：
分别以β、ZSM-5和USY分子筛为载体，采用浸渍法制备了锰铈催化剂，对其低温NH3-SCR反应性能进行了评价，并采用XRD、BET、NH3-TPD、H2-TPR以及XPS对催化剂进行了表征。结果表明，三种分子筛负载的锰铈催化剂均具有较好的低温NH3-SCR反应活性，其中，Mn-Ce/USY的催化性能最好，在107℃时NOx转化率可达到90%。负载锰铈后催化剂的比表面积和孔体积均有所下降；活性组分MnOx主要以无定型态分布于催化剂表面，且在ZSM-5上检测到聚集的CeO2。催化剂表面弱酸对低温NH3-SCR反应起主要作用，催化剂表面上活性组分的表面浓度和氧化态明显不同，较高的Mn4+/Mn3+原子比和吸附氧表面浓度对提高催化剂的低温NH3-SCR反应活性有利。
分别以β、ZSM-5和USY分子筛为载体，采用浸渍法制备了锰铈催化剂，对其低温NH3-SCR反应性能进行了评价，并采用XRD、BET、NH3-TPD、H2-TPR以及XPS对催化剂进行了表征。结果表明，三种分子筛负载的锰铈催化剂均具有较好的低温NH3-SCR反应活性，其中，Mn-Ce/USY的催化性能最好，在107℃时NOx转化率可达到90%。负载锰铈后催化剂的比表面积和孔体积均有所下降；活性组分MnOx主要以无定型态分布于催化剂表面，且在ZSM-5上检测到聚集的CeO2。催化剂表面弱酸对低温NH3-SCR反应起主要作用，催化剂表面上活性组分的表面浓度和氧化态明显不同，较高的Mn4+/Mn3+原子比和吸附氧表面浓度对提高催化剂的低温NH3-SCR反应活性有利。
2016, 44(3): 279-286.
摘要：
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.
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.
2016, 44(6): 732-737.
摘要：
考察了碱处理、先碱后两步酸处理对HZSM-5分子筛物化性质以及苯与甲醇烷基化反应性能的影响。结果表明, 碱处理在脱除分子筛中非骨架硅的同时, 提高了晶孔的利用率, 也中和了分子筛的强酸中心, 使催化剂活化甲醇的能力减弱, 苯与甲醇反应活性降低; 先碱后两步酸处理既脱除了分子筛中的非骨架铝, 也恢复了一部分强酸中心, 提高了苯与甲醇的反应活性。进一步考察了先碱后两步酸处理中不同碱浓度的影响, 结果表明, 适宜浓度的碱处理后再两步酸处理, 一方面, 能脱除分子筛的非骨架硅铝物种, 使分子筛的颗粒粒径更加均匀; 另一方面, 分子筛的强酸中心有所减少, 降低了催化剂的积炭失活速率, 苯转化率提高15%以上。
考察了碱处理、先碱后两步酸处理对HZSM-5分子筛物化性质以及苯与甲醇烷基化反应性能的影响。结果表明, 碱处理在脱除分子筛中非骨架硅的同时, 提高了晶孔的利用率, 也中和了分子筛的强酸中心, 使催化剂活化甲醇的能力减弱, 苯与甲醇反应活性降低; 先碱后两步酸处理既脱除了分子筛中的非骨架铝, 也恢复了一部分强酸中心, 提高了苯与甲醇的反应活性。进一步考察了先碱后两步酸处理中不同碱浓度的影响, 结果表明, 适宜浓度的碱处理后再两步酸处理, 一方面, 能脱除分子筛的非骨架硅铝物种, 使分子筛的颗粒粒径更加均匀; 另一方面, 分子筛的强酸中心有所减少, 降低了催化剂的积炭失活速率, 苯转化率提高15%以上。
2016, 44(9): 1034-1042.
摘要：
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。
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。
2017, 45(1): 113-122.
摘要：
针对中低温锅炉烟气脱硝技术需求的特点，采用等体积浸渍法，以V2O5为活性组分、MoO3为助剂，制备了高钒高钼含量的V2O5-MoO3/TiO2型粉末和平板式SCR脱硝催化剂，考察了活性组分和助剂含量对催化剂活性以及抗SO2和H2O中毒性能的影响，对反应前后的催化剂进行了微观表征，并针对最优催化剂研究了其在不同烟气工况下催化剂的脱硝性能。结果表明，提升V2O5负载量可以有效提高催化剂的脱硝活性；MoO3助剂的添加也可以提高催化剂的脱硝活性。XPS、XRF、FT-IR等表征结果表明，MoO3的含量会影响催化剂中V4+/V5+的比值，其相对含量的增加有利于催化剂中非化学计量钒物种的形成以及化学吸附氧比例的增加，钼与钒物种间的交互作用是抑制SO2和H2O对催化剂的毒化作用的关键。3V2O5-10MoO3/TiO2平板式催化剂在温度为200℃、空速为3 500 h-1含SO2和H2O烟气条件下，经30 d连续反应，脱硝效率稳定维持在82%左右，该催化剂在中低温下具有优异的抗SO2和H2O中毒性能以及稳定性。
针对中低温锅炉烟气脱硝技术需求的特点，采用等体积浸渍法，以V2O5为活性组分、MoO3为助剂，制备了高钒高钼含量的V2O5-MoO3/TiO2型粉末和平板式SCR脱硝催化剂，考察了活性组分和助剂含量对催化剂活性以及抗SO2和H2O中毒性能的影响，对反应前后的催化剂进行了微观表征，并针对最优催化剂研究了其在不同烟气工况下催化剂的脱硝性能。结果表明，提升V2O5负载量可以有效提高催化剂的脱硝活性；MoO3助剂的添加也可以提高催化剂的脱硝活性。XPS、XRF、FT-IR等表征结果表明，MoO3的含量会影响催化剂中V4+/V5+的比值，其相对含量的增加有利于催化剂中非化学计量钒物种的形成以及化学吸附氧比例的增加，钼与钒物种间的交互作用是抑制SO2和H2O对催化剂的毒化作用的关键。3V2O5-10MoO3/TiO2平板式催化剂在温度为200℃、空速为3 500 h-1含SO2和H2O烟气条件下，经30 d连续反应，脱硝效率稳定维持在82%左右，该催化剂在中低温下具有优异的抗SO2和H2O中毒性能以及稳定性。
2018, 46(2): 179-188.
摘要：
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M（M=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%。
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M（M=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%。
2013, 41(08): 1003-1009.
Abstract:
2009, 37(04): 501-505.
Abstract:
