Abstract: Chinese Xundian, Mongolian Shiveeovoo lignites and Khoot oil shale are pyrolyzed under synthesis gas (SG) at temperature range from 400 ℃ to 800 ℃ for lignite and from 300 ℃ to 600 ℃ for oil shale with heating rate of 10 ℃／min in a fixed bed reactor. The results were compared with those obtained by pyrolysis under hydrogen and nitrogen. The results showed that unlike pyrolysis at high pressure, there are only slight different in the yields of char and tar among pyrolyses under various gases at room pressure for lignite, while higher liquid yield with lower yields of char and gas was obtained in pyrolysis of oil shale under SG and H2 than under N2. It is found that the pyrite S can be easily removed to partially convert to organic S under various gaseous atmosphere and the total sulfur removal for oil shale is much less than lignite, which might be related to its high ash content. The higher total sulfur removal and less organic S content in the presence of SG in comparison with those under N2 and even under H2 in pyrolysis of Xundian lignite might result from the action of CO in SG. However, CO does not show its function in pyrolysis of Khoot oil shale, which might also be related to the high ash content. The results reported show the possibility of using synthesis gas instead of pure hydrogen as the reactive gas for coal hydropyrolysis.
Abstract: Minerals inherently presented in coal and ironcontaining compounds externally added have an important influence on the formation and release of HCN—one of the NOx precursors during coal pyrolysis. The experiments on the pyrolysis of raw coal and demineralized coal with different carbon contents and ironcontaining compounds were carried out in a fixed bed quartz reactor with the temperature programmed. The influencing factors of HCN formation and release during coal pyrolysis were examined. The results show that the effect of ironcontaining compounds in coal on HCN release depends on the coal types. And the iron added to coal by impregnation and precipitation method can significantly reduce the formation of HCN for lower coalification coals . Additionally, the effects of particle size and reaction time on HCN formation during pyrolysis of coal with iron were also studied.
Abstract: This paper mainly described the influence of normal and trace elements on hydrocarbon generating potential and organic carbon determination of Jurassic low rank coal from the Liudaowan coalfield, Zhungaer, Xinjiang, China. Coal samples were examined using inductively coupled plasmaatomic emission spectrometry and Xray fluorescence spectrometry. The results show that almost all of the major elements and their minerals, except some elements which play as a catalyst in processing of coal derived hydrocarbon, have passive roles in the processing obviously. These are likely attributed to the elements and their minerals reducing the content of organic matter in coals. However, trace elements play complex roles in the processing. The reasons are not only the difference of organic affinity between trace element and coal chemical composition, but also trace elements playing as a catalyst in pyrolysis of coal macromolecule. Additionally, some trace elements in coals, which indicate the paleoclimate and the types of bog in coalforming period, can also show hydrocarbon generating potential of coal, such as Cu which has a strong affinity to organic macromolecule in coals. Cu is a facies element, and may be an indicator element of hydrocarbon generating potential．
Abstract: In allusion to the desulfuration characteristic of coal ash, the desulfuration of the ash and CaO, Al2O3 added to Changguang coal with different proportions at high temperature was studied.Sulphoaluminate as the main desulfuration product was analyzed by Xray diffraction and SEM visualization.Experimental results indicate that higher proportion of ash added can improve the desulfuration efficiency.The sulphoaluminate content in residue increases with increasing the addition of ash. The desulfuration efficiency of the additive CaO and Al2O3 is up to 24% at 1300℃, at the same time the sulphoaluminate is detected in the residue.
Abstract: The combustion of three types of sewage sludges from different municipal wastewater treatment plants was studied by the thermal gravimetric analysis at a heating rate of 30℃/min. Effects of wastewater treatment process and sludge treatment process on the organic compositions and combustion characteristics were discussed. It is observed thatthe anaerobic process can make the organics structure in the sewage sludge so complicated that the higher temperature of combustion is required. Comparative study on pyrolysis in N2 and combustion was done by TGAFTIR analysis. During pyrolysis the sewage sludge decomposes to lower molecular weight volatile compounds. Oxygen can accelerate the decomposition. The pyrolysis temperature of sewage sludge lies in the range of 200℃～500℃. The main gas products include H2O, CO2, CO and hydrocarbons. CO2 is generated not only in the temperature range 200℃～500℃ but also at 750℃ because of the decomposition of inorganic compounds.
Abstract: The effects of ionic liquids on viscosity, hydrocarbon composition and average molecular weight of heavy oils are investigated. The results indicate that ionic liquids have good viscosity reduction property for heavy oils. After reaction with ionic liquids, the amount of saturates, aromatics and resins increase, while asphaltene decreased. This leads to average molecular weight and viscosity of heavy oil decreased. The results also indicate that metal ion modified ionic liquids have catalytic effect on the upgrading reaction of heavy oils.
Abstract: Sulfur compounds in VGO of SCO（Synthetic Crude Oil） from Canadian oil sand bitumen were identified with GCPFPD and GCMS methods. The sulfur compounds in VGO of SCO are mainly C3~7dibenzothiophene, while those in FCC liquid products are short chain dibenzothiophene and a few alkylated benzothiophene and alkylated thiophene, and the percentages of these three sulfur compounds are 82.04%, 13.42% and 0.56%, respectively, and they are difficult to be removed by hydrogenation. The mixtures of VGO which mixed with SCO and Dagang in different proportion were processed in FCC reactor. With the increase of proportion of mixtures, the sulfur content of alkylated benzothiophene and alkylated thiophene in FCC liquid products reduce gradually, and the dominant part is short chain dibenzothiophene, especially 4-MDBT indicating the characters of hydrogenation of SCO. The content of sulfur in liquid products and diesel distillate increases, while it is reduced in gasoline distillate.
Abstract: The watersoluble molybdenum catalyst dispersed in oil by using two different methods of dispersion and sulfuration, which was separated and characterized. It shows that the average particle size of the molybdenum crystal is smaller while the emulsion breaking and sulfurizing at 300℃ or at 200℃. The watersolubility molybdenum turns into MoS2 while sulfurizing at 100℃. By using two different methods of dispersion a lower degree of crystallinity is obtained, but the degree of crystallinity increases obviously while sulfurizing at 300℃. The results also show that the coke restraining ability of the catalyst increases when the sulfuration time is prolonged. While the sulfuration time is beyond 2 hours, the coke restraining ability of the catalyst will go steadily with time.
Abstract: Oxidative desulfurization of thiophene by phase transfer catalysis has been investigated with hydrogen peroxideformic acid as the oxidant, thiophene in nheptane as model compound of light oil. It was shown that the desulfurization rate of thiophene was 86.36%, under the conditions of water/oil ratio being 1∶1, after1.5h at temperature of 45℃ by TBAB. From the kinetics investigation, it was shown that when the model compound was oxidized by hydrogen peroxideformic acid with TBAB as phase transfer catalyst, the reaction was pseudo firstorder reaction with rate constants of K30℃=0.6152h-1, K40℃=1.2672h-1, and K50℃=0.8581h-1. The essential process of catalytic oxidation is the transfer of oxidizing active ingredients RCOOO- from water phase to oil phase by Q+, and the cycling models of oxidative desulfurization of thiophene by phase transfer catalysis(Q+X-) is builted.
Abstract: The effect of solvents on the reaction performance of FischerTropsch synthesis under supercritcal and nearcritical conditions was studied in a fixed bed reactor. Two kinds of solvents: pure solvents (n-hexane and n-pentane) and mixed solvents (the solvent consists mostly of n-hexane and some content of C5 to C10 normal paraffins and normal olefins) were chosen as the solvent. The catalyst used was a SiO2 supported cobalt catalyst. The results showed that the partial pressure of n-hexane had little influence on the CO conversion when total pressure and syngas partial pressure were kept constant. 1olefins content in the products, however, increased with increasing partial pressures of n-hexane. 1olefins content in the products under supercritical condition was obviously higher than that under nonsupercritical conditions. Similar CO conversion, CH4 and CO2 selectivities and hydrocarbon distribution were obtained in different pure media: n-pentane and n-hexane. 1olefins content in n-pentane was slightly lower than that in n-hexane. Compared with pure n-hexane solvent, the solvent with mainly n-hexane and some C5~10 components had similar effects on CO conversion, CH4 and CO2 selectivities, and hydrocarbon selectivity of the products. This result suggested that the recycle of the supercritcal solvent contained some content of lighter fractions (such as C5~10) produced in the FT process is possible for reducing the amount of supercritical solvent during supercritical FT process. The binary mixed solvent (25% n-hexane/75% n-decane) showed much higher 1olefins selectivity than the pure n-hexane probably because of its higher solubility to heavier products.
Abstract: In order to promote mass transfer and realize products separation from slurry, reaction performance of CuCr/CH3ONa catalyst used for the lowtemperature methanol synthesis was firstly examined in the bubble column slurry reactor with a flash column(BCSR/FC). The reaction system includes the reaction section of 39mm id. and 4800mm height and the enlarged section of 147mm id and 1200mm height in BCSR,FC of 147mm id. and 1640mm height and a slurry recirculating pump. The initial slurry was composed of the required amounts of sodium methoxide solution and CuCr catalyst and emulsifier OP10 as well as the balanced liquid xylene medium. The results showed that the BCSR/FC can be operated at 4.2MPa~4.6MPa,110℃~120℃ (reaction section)and 100℃~110℃(enlarged section),inlet gas velocity 0.35cm/s~0.40cm/s for BCSR, 0.25MPa~0.4MPa, 80℃~90℃ for FC and slurry recirculation rate of 50L/h. The results showed that the conversions of CO+H2, CO and H2 were decreased from their highest of 71.0%,79.1% and 67.5% to 17.8%, 35% and 12.1% during operation test over 100h respectively. The stability of the catalyst system is poor although its initial activity is quite high.This is probably due to the consumption of CH3ONa caused by the side reaction CH3ONa + HCOOCH3→CH3OCH3 + HCOONa. Liquid products were composed of DME of 1.23%, methanol of 79.52% and MeF of 19.25%. Selectivity of Methanol + MeF is more than 98%.Its yields were 0.168g/g cat·h based on all CuCr catalyst in the system and 0.336 g/gcat·h only based on the CuCr catalyst in BCSR.
Abstract: Sodium carbonate impregnated activated carbon (IACⅠ) and another highly effective desulphurization agent (IACⅡ)were made by impregnation. To compare the ability of AC, IACⅠand IACⅡfor removal of hydrogen sulfide, the breakthrough curves for removal of low concentration H2S on fixed bed were measured. The effects of relative humidity and inlet concentrations on the removal process were investigated. To simulate the breakthrough curves a one-dimension model for fixed beds was developed and numerically solved. The effective diffusion coefficients of H2S were evaluated by fitting the experiment breakthrough curves with the calculated ones. The results show that IACⅡhas the best performance, and its effective diffusion coefficient is higher than that of IAC I. Higher relative humidity is of benefit to improve the sulfur capacity, but the effective diffusion coefficients decrease slightly. With the increasing of inlet H2S concentrations, the effective diffusion coefficients increase, the breakthrough time gets shorter and the sulfur capacity decreases slightly.
Abstract: The Regenerable Zinc titanate sorbent is one of the leading candidates for hot coal-derived gas desulfurization. The effect of the regeneration temperature, O2 concentration and sorbent granular size on the regeneration reactivity of Zn2TiO4 sorbent were investigated by using the thermogravimetric analyzer. Zinc sulfate formed through side reactions was inferred from TGA curves and was confirmed by the XRD analysis when the sorbent was regenerated at higher concentration of the oxygen and lower temperature(<750℃). The reasonable regeneration conditions should avoid the sulfate formation. Regeneration kinetic studies were also performed at regeneration temperature from 725℃ to 800℃. Higher regeneration temperature and O2 concentration, smaller granular size can increase the regeneration rate. The order of O2 in the reaction can reasonably be assume to be 1. Kinetic model tests show that the regeneration process can be well fitted by the shrinking core model. The kinetic controlling steps transfer with the sorbent conversion. The chemical reaction rate is the controlling step at the early regenerating stage (<65%), while the inner diffusion through the product layer play a dominant role at the latter regenerating stage (>75%). The reaction rate constants and the effective diffusivities were calculated according the model. The apparent activation energy of chemical reaction and corresponding frequency factor are 19.11kJ/mol and 8.01×10－2m/s, respectively. While the diffusion activation energy and corresponding frequency factor are 48.84kJ/mol and 3.12×10－4m2/s, respectively.
Abstract: Temperature profiles of fixedbed with Ni/Al2O3 catalyst were studied during the trireforming of methane in the temperature range of 750℃～950℃, 1 atm, and space velocity from 2000h－1 to 20000h－1. The effects of the furnace temperature (tf), space velocity, and the composition of feed stock on the thermal distribution were investigated. The results indicated that temperature grads of catalyst bed in the trireforming were lower than that in partial oxidation of methane. The temperature near the catalyst bed inlet (tmax) was 80℃ higher than tf at CH4/CO2/H2O/O2=50/12.5/12.5/25 and 2000h－1, whereas the temperature near the catalyst bed outlet was close to tf.Δtmax ( = tmax－tf) decreased with the decrease of space velocity (Δtmax=80℃ at 20000h－1; Δtmax=30℃ at 2000h－1). No distinct temperature grads were found near the catalyst bed inlet when there was no oxygen in feed. Under specific condition, tmin (the lowest temperature in the catalyst bed), which was about 30℃~40℃ lower than tf, can be observed in the bed. According to thermal distribution of the bed, the catalyst bed can be divided into three zones, oxygen adequate zone, oxygen inadequate zone, and oxygen absent zone. In oxygen adequate zone, methane combustion occurs only. In oxygen absent zone, methane reforming (carbon dioxide and steam reforming) takes places only. However, in oxygen inadequate zone, both reforming and partial oxidation of methane are present.
Abstract: The experiment of hydrogen production from sorption enhanced steam methane reforming (SE-SMR) were done in a laboratoryscale fixedbed reactor system, and the effects of temperature, CH4 flow rate, particle size and different sorbents on the reaction processes of SE-SMR were investigated. The results indicate that the optimal reaction temperature for SE -SMR was affected by the reaction thermodynamic and kinetics. With CaO as sorbent, the optimal reaction temperature is in the range of 600 ℃～700 ℃ at atmosphere pressure. The flow rate of CH4 should be determined based on the sorbent amount in reactor and the required time for sorption enhanced period. The particle size should be larger than 90 μm and pure CaO and new Cabased CO2 sorbentCaO/Ca12Al14O33 both achieve good sorption enhanced effects.
Abstract: The effects of CeO2 and/or CaO as promoters on the physicochemical properties and the catalytic performance over Ni/MgOAl2O3 catalyst for partial oxidation of methane to syngas were studied by means of BET, XRD, H2TPR, TEM and reaction activity evaluation. Compared with the catalyst without promoters, the catalyst promoted by CeO2 or CaO alone exhibited better reducibility of nickel species, and the one promoted by CaO showed better catalytic activity. When both of CeO2 and CaO were added to modify the Ni/MgOAl2O3 catalyst, an obvious synergetic effect between CeO2 and CaO were detected. It was deduced that the formation of CaOCeO2 solid solution could result in a better dispersion of active nickel species and promote the conversion of Ce4+ to Ce3+ species, thus reduced the size of nickel crystallites efficiently. Better oxygen adsorption ability, more oxygenvacant sites and more migration of oxygen anions could benefit oxygen exchange between NiO and CeO2. The above effects were contributed to higher CH4 conversion, CO selectivity and H2 selectivity over the catalyst promoted with CeO2 and CaO in the partial oxidation of methane.
Abstract: The supports of magnesiumaluminum composite oxides were prepared by coprecipitation method using magnesium nitrate and aluminum nitrate as starting materials with ammonia solution as pH agent. The effects of magnesiumaluminum ratio, the kind of pH agent, pH value in the hydrolytic process, reaction temperature, calcination temperature, and crystallization temperature on the physicochemical characteristics of the magnesiumaluminum composite oxides were studied systematically in this paper. The selective hydrodesulphurization (SHDS) properties of the catalyst supported on the magnesiumaluminum composite oxides were investigated with the SHDS of residual fluid catalytic cracking (RFCC) gasoline as probe reaction. The results showed that the support of magnesiumaluminum composite oxides which was prepared at the ratio of magnesium to aluminum (Mg/Al) being 10, reaction temperature of 80℃ and the pH of 9.5, had proper specific surface area, uniform pore distribution and integrated crystal structure with high degree of crystallization. The catalyst supported on this kind of composite oxides performed well for SHDS of the RFCC gasoline.
Abstract: A series of cobalt or manganese incorporated aluminophosphates (CoAPO-5 and MnAPO-5) with different metal contents were hydrothermally synthesized. Various methods such as XRD, SEM, nitrogen adsorption, thermogravimetric analysis and UVVisible diffusion reflectance spectra were used to characterize the structure and crystallinity of the aluminophosphates as well as the chemical state of Co or Mn in the framework of molecular sieves. Moreover, the selective oxidation of cyclohexane was investigated with CoAPO-5 and MnAPO-5 as catalyst. The metal content incorporated in the molecular sieves has a vital influence on the structure, crystallinity and templates removal of CoAPO-5 and MnAPO-5. High crystallinity was obtained with a Me/P (Me = Co or Mn) mole ratio lower than 0.10, while higher metal content may result in a great deal of extra framework species. The tetrahedral Co2+ or Mn2+ in the lattice framework of molecular sieves was evidenced, which could be partially oxidized to Co3+ or Mn3+ to form redox centers upon calcination. The catalytic tests proved that CoAPO-5 and MnAPO-5 are effective catalysts for the selective oxidation of cyclohexane to cyclohexanol and cyclohexanone at low temperature (130℃) using molecular oxygen as oxidant. MnAPO-5 exhibits higher activity for alkane oxidation than CoAPO-5, but gives more products of deep oxidation. The products distribution was also affected by the reaction duration and the contents of the metal ions. CoAPO-5 with a Co/P mole ratio of 0.05 exhibited the best activity and selectivity; after the reaction at 130℃ lasted for 24h, the selectivity to cyclohexanol and cyclohexanone reached 88.5% with the cyclohexane conversion of 14.7%.
Abstract: The recycled oil from coal liquefaction was separated into three fractions (saturates, aromatics and polar fraction) by liquid chromatograph according to group composition. Each fraction was analyzed qualitatively by 1HNMR spectra, then the aromatic fraction was characterized using gas chromatograph/mass spectrometer (GCMS). It shows that liquid chromatograph is well used to separate coal liquefaction oil with high repeatability and high recovery yield. Aromatic fraction with carbon number from C10 to C21 mainly includes dicyclic, tricyclicand tetracyclichydrogenation aromatic compounds such as tetrahydronaphthalene, hydrophenanthrene, hydropyrene and their alkyl substitution compounds and so on.
Abstract: Based on the specifications of ASTM D571095 and BSI BS3690 for Trinidad Lake Asphalt (TLA) modified asphalt, two residues （CLA1 and CLA2）from direct coal liquefaction (DCL) were evaluated for using as high grade paving asphalt modifier. TLA was used as comparison. The results show that CLA1 and CLA2modified asphalt with 7% of CLA1 or CLA2 addition has similar modification ability as 20% TLAmodified asphalt. The modified asphalts meet the specifications for 40~55 or 50 penetration grade. The penetration ratio of CLA2modified asphalt after TFOT is significantly higher, which indicates its supreme ability to against the temperature aging. Preliminary study implies that DCL residues may be a suitable alternative additive for producing TLAtype modified asphalt. Furthermore it was also found that with increasing amount of CLA1 or CLA2 addition the softening point of the modified asphalts increase and the penetration value and the ductility decrease.
Abstract: The activity of FCC additives of Zn(Al2O)2 with different ZnO contents were prepared by solgel, and the desulfurization effect of additives in the gasoline was evaluated in a micro reactor. The results indicate that the additive with 10% ZnO shows the best desulfurization activity, the conversion of thiophene reaches 12.7%. The activity of the additives with CeO2 was also studied, which can remove 18.13% thiophene from gasoline in the micro reactor. The crystals and acidic of additives were studied by XRD and Infrared Ray. IR results show that weak Lewis acid amounts affected activity of the additives. XRD results indicate that the best crystal of Zn(Al2O)2 spinel is not in favor of removal of thiophene. When the crystallinity is low, there are more active sites with more adsorption activity. The additives show the better desulfurization effects when the adsorption sites and L acid sites reach balance.
Abstract: Coprecipitation method was employed to prepare LaMnAl11O19 catalyst for methane combustion. Sodium carbonate was used as precipitator in the process. The influences of precipitation temperature on the structure and property of the catalysts were investigated by XRD、SEM、BET techniques. The optimal calcination temperature of the catalysts was determined. The results show that the crystal phase and activity for methane combustion are greatly affected by precipitation temperature, and hexaaluminates with high activity were formed when catalysts were calcinated at 1200 ℃ for 4h. Typically at the precipitation temperature of 90 ℃, the specific surface area of the catalyst is about 19.6 m2/g, and the lightoff temperature (T 10% for methane combustion is 432℃ and the full conversion temperature is 712℃.
Abstract: The possibility of using activated carbon to remove sulfurcontaining species in oil was explored. The desulfurization performance of activated carbons pretreated under different conditions was evaluated by measuring the adsorption isotherms and using a model oil in a batchtype adsorption device. The sulfur content in the model oil is 440×106. The results show that the adsorption capability of thiophene on the activated carbon pretreated by oxidizing in HNO3 at 120 ℃ is superior to that of other activated carbons treated by other methods. The optimum adsorption performance can be achieved at the temperature of 20 ℃, the adsorption time of 3 h, and the adsorbent/ oil ratio of 0.09 g/g. The adsorption isotherms of thiophene on the activated carbons fit the Freundlich model and equation satisfactorily. The thiophene adsorption on the activated carbon is a spontaneous.
Abstract: The selective catalytic reduction (SCR) of NOx using MnOx and CeO2 supported on viscosebased active carbon fibers (ACF) at 120℃～270℃ relatively lower than the temperature when using V2O5/TiO2anatase catalyst was studied. As a result, CeO2/ACF shows a better catalysis than MNOx/ACF, which is not affected by the reaction temperature. NO conversion of 85% is reached with the 10%CeO2/ACF catalyst at the whole temperature window. Furthermore, a series of MnOxCeO2/ACF composite catalysts were studied. The results show that the loading method of catalyst affects its activity.
Supervisor：Chinese Academy of Sciences
Sponsors by：Shanxi Institute of Coal Chemistry, Chinese Academy of Sciences Chinese Chemical Society
