Abstract: This article discusses the processing options for hydrogen production in conjunction with hydrogen utilization, fuel cells, and mitigation of CO2 emissions. It should be emphasized that molecular hydrogen is an energy carrier but not a primary energy resource. Thus H2 must be produced using hydrogen and energy resources. By atomic hydrogen and energy sources, hydrogen can be produced from coal (gasification, carbonization), natural gas and propane gas (steam reforming, partial oxidation, autothermal reforming, plasma reforming), petroleum fractions (dehydrocyclization and aromatization, oxidative steam reforming, pyrolytic decomposition), biomass (gasification, steam reforming, biological conversion), and water (electrolysis, photocatalytic conversion, chemical and catalytic conversion). For fossil fuel-based H2 production in stationary plants such as coal gasification and natural gas reforming, it would be desirable to develop new approaches that produce hydrogen in a more economical and environmentally-friendly process that also includes effective CO2 capture or CO2 utilization as an integral part of the system. A concept called CO-enriched gasification is proposed here for H2 production from gasification of coal and biomass that may be studied further. For mobile fuel processor, there are major challenges in the development of (1) fuel processor for on-site or on-board production of H2 that meets the stringent requirement of CO (<10×10－6 (v/v)) and H2S (<20×10－9 (v/v)) for H2-based proton-exchange membrane fuel cell system, and (2) fuel processor for synthesis gas production for solid-oxide fuel cells that use hydrocarbon fuels. The sulfur contents of most hydrocarbon fuels are too high for use in fuel cell reformer and in anode chamber, if when such fuels meet EPA sulfur requirements in 2006～2010 for automotive vehicles. Removal of organic sulfur before reforming and cleaning inorganic sulfur after reforming would be important for H2 and syngas production for fuel cells, but conventional desulfurization methods are not suitable for fuel cell applications. Hydrogen energy and fuel cell development are closely related to the control of CO2 emissions.
Abstract: Denmark has the best knowledge and know-how of converting straw to energy and manufacturing straw fired boiler plant, from which many concepts may be learned. In this paper, an overview of power production from the annual biomass, the problems of the biomass-based plants and the corresponding research activities are presented.
Abstract: Catalytic effects of Na, Ca, Fe and their composites on NO-char reaction in the presence of SO2 were investigated by Temperature Programmed Reaction (TPR) technique. The catalytic activity order of three metals is Fe>Ca>Na in the same conditions. SO2 may participate in the oxygen-transfer process to influence the metal catalytic effect in NO-char reaction. For three types of metal loaded catalysts, effects of SO2 concentration on their catalytic activities are different. The catalytic activity of Na loaded char is influenced most by the SO2 concentration. 2% Na or Fe loaded chars and 3% Ca loaded char have the highest NO conversion activity in the presence of SO2. Na-Fe and Na-Ca composite catalysts have higher catalytic activity. Synergistic effect of Na-Ca and Na-Fe may be responsible for the high NO conversion activity of these bimetallic catalysts in the presence of SO2.
Abstract: Ideal coal water slurry (CWS) with maximum coal loading should be relatively stable at static stability and good rheological behavior. Additives have usually been used to improve the slurryability and rheological behavior as well as static stability of CWS to meet requirement of its transportation, storage and combustion in industrial application. The selection of high efficient additives is one of the key steps for preparation of CWS. Therefore, the investigation of the relationships between the properties of CWS and molecular structure of additives plays an important role in selecting high efficient additives. In this paper, 7 additives with different structural characteristics and 8 coals are selected to evaluate the correlation between the structural characteristics of additives and the properties of CWS. The results indicate that introducing methyl substitute into the monomer of polynuclear aromatic sulphonate promotes the rheological behavior and the static stability of CWS, but at the same time it is unfavorable for the slurryability of CWS. The presence of benzyl substitute improves the slurryability of CWS prepared with coals of low content of Oad, but it is unfavorable for improving the static stability of CWS. CWS with high coal loading could be prepared by using both low rank coals with a lot of polar oxygen groups and humate additive with high degree of sulphonation. It is also found that additives of humate and lignosulfonate with high degree of sulphonation increase the static stability of CWS prepared by coals with high content of Vdaf.
Abstract: Based on experimental data of coal slurry, three BP neural network models with 8, 7 and 5 input factors, were set up for predicting the slurry concentration. Three BP neural networks’ algorithm was Levenberg-Marquardt algorithm, and their learning rate was 0.01. The hidden neurons number was settled by practical training effect of the networks. The hidden neurons number of BP model with 8, 7 and 5 input factors is 27, 30 and 24, respectively. Two data treated method were tested by seven input factors network model, which proves that the first method is the better one. The mean absolute error of the neural network models with 5, 7 and 8 factors is 0.53%, 0.50% and 0.74%, respectively, while that of the existed regression model is 1.15%. This indicates that the neural network models, especially the 7 factors’ model, are effective in predicting the slurry. The HGI input neuron in eight input factors’ model affects the prediction result because of its interference to other input factors. The effect of H and N in coal on the slurry is slight.
Abstract: The gasification of Beisu， Shenfu， Xinzhou and Luan coal chars with CO2 at 970 ℃~1 165 ℃ was studied by the isothermal thermogravimetric analysis(TGA) under the condition of chemical reaction control. The effects of coal types, temperature and ash content in coal on the char gasification with CO2 were examined. The random pore model, the unreacted shrinking core reaction model and the integrated model were tested by the experimental data respectively. The results show that the random pore model is the best to fit the experiment data among three kinetic models, which has a correlation coefficients of 0.99 both at 1 066 ℃ and 1 165 ℃. The kinetic parameters (E, k0, A0, ψ) are obtained. A0 is bigger when the gasification temperature is higher. ψ as the initial pore structure parameter is affected by the change of pore structure at different pyrolysis temperatures. It becomes smaller when the gasification temperature increases.
Abstract: The catalytic gasification kinetics of low active Fujian anthracites（Volatile matter:3.56%~4.35%）by carbon dioxide was carried out in the fixed bed reactor of 18 mm inside diameter. The reaction conditions of eliminating both internal and external diffusion effects were determined. Using sodium carbonate as the catalysts, the relationships of coal conversion with reaction time for three low active anthracites (Yong′an Fengshai coal, Yong′an Jiashai coal and Yongding coal ) were explored within the temperature range from 750 ℃ to 907 ℃. Using potassium carbonate and black liquor of paper pulp plant as the catalysts, the relationships of coal conversion with the reaction time for Yongding coal were also studied. The kinetic parameters including the reaction rate constant, the reaction activation energy and the pre-exponential factor were obtained by using the homogeneous model and the shrinking core model. Comparing with the results from the thermogravimetric balance, the reaction rate constant, the reaction activation energy and the pre-exponential factor from the fixed bed are higher than those obtained from the thermogravimetric balance, which could be caused by the higher mass transfer rate of carbon dioxide to the coal surface and higher heating rate in the fixed bed.
Abstract: In order to investigate the characters of plasma aided coal gasification in the industry-scale equipment, the tests with changing feeding rate, steam output pressure, feeding gas (air ) flux, input power of plasma generator and the addictives (CaO and CaCO3) were carried out with Datong coal. The produced gas components were analyzed by gas chromatography. And the optimal process conditions, such as, the feeding rate of 150 g/min, the feeding gas (air or oxygen) flow of 18 m3/h, the output power of plasma generator of 100 kW, the steam output pressure of 0.3MPa are obtained. When the contents of CaO and CaCO3 in the whole feed are 10% and 5% respectively，the experimental data show their catalytic effect is the best. Considering the molar mass of CaO and CaCO3, it is concluded that the catalytic effect of CaO is more important than the reduction of CO2 in the gasification.
Abstract: Using CO2 as the gasification agent, the gasification reactivity of the petroleum coke and the mixtures with Houbulian coal chars was studied in a self-made tubular reactor under normal pressure and at temperature ranging from 1 200 ℃ to 1 500 ℃. The difference of carbon structure ordering between petroleum coke and coal char processed at high temperature was analyzed by using XRD. The results show that the gasification rate of petroleum coke decreases rapidly when the carbon conversion rate is higher than 70% and the gasification temperature is over 1 300 ℃. The higher the gasification temperature is, the faster the gasification rate of petroleum coke declines. The gasification reactivity of the mixture of petroleum and coal char is different from that of pure petroleum coke or pure coal char. With the variation of the ratio of petroleum coke to coal char, the inflexion varies because of the different reactivity between petroleum coke and coal char. With the increase of gasification temperature, the decrease of gasification rate of the petroleum coke results in the appearing of inflexion at higher carbon conversion. The XRD test indicates that after being handled at high temperature, the degree of carbon structure ordering in petroleum coke is greater than that in coal char. The carbon structure ordering obviously at high temperature is an important reason to lead to the sharp reduction of petroleum coke gasification rate.
Abstract: Experiments on pyrolysis of cellulose added with calcium chloride (CaCl2) were done on a thermogravimetric (TG) balance to study the catalytic mechanism of the process. Compared with the TG curves of pure cellulose pyrolysis, those added with CaCl2 show that CaCl2 has a strong effect on the formation of char, which increases the char yield from 5% to above 10%. In addition, it affects the formation of active cellulose by moving TG curve towards lower temperature, and leads to a small weight loss peak at the initial stage of decomposition process, which reveals the emission of small gas are improved in the process of de-polymerization of long chain biomass molecule. By kinetic analysis, the pyrolysis process of cellulose with CaCl2 is divided into three stages, respectively, corresponding to the formation of AC, carbonization and conversion into volatiles, which control the weight loss process sequentially. Based on the Broido-Shafizadeh model, those kinetic parameters calculated by narrow temperature zone method show that CaCl2 enhances all these three reactions. Especially in the low temperature the formation of char is catalyzed strongly, whose active energy has a sharp decrease. Because of the catalytic selectivity of CaCl2 on different reactions, CaCl2 has an especial effect on the formation of char, and decreases the emission of gas during the carbonization process, which indicates the char catalyzed by CaCl2 has high aliphatic degree.
Abstract: A bio-diesel fuel sample, methyl esters from soybean oil (SME), was prepared by basic catalysis and transesterification. The important characteristics such as acid value, free glycerol, viscosity (ν), total glycerol, ash and phosphor content were determined. The v and the low-temperature flowing properties (LTFP) such as solidification point (SP), pour point (PP) and cold filter plugging point (CFPP) were tested by standard petroleum methodologies. LTFP of SME is hardly influenced by methanol, water and glyceride that exist in SME when their contents are less than their specifications required. When SME is cooled, the saturated fatty acid methyl esters (FAME) in SME will co-crystallize first. Thus LTFP of SME is greatly influenced by the saturated FAME in SME. Then the approaches for improving LTFP of SME were explored. Five cold-flow additives, No.0 diesel fuel (DF0), No-20 diesel fuel (DF-20) and ethanol were tested. DF0 can improve ν of SME, but can not greatly affect LTFP of SME. DF-20 and ethanol can greatly improve CP, PP, CFPP and ν of SME. Three cold-flow additives can greatly reduce SP and PP of SME, but only one can improve CFPP a little. All five cold-flow additives can increase ν of SME.
Abstract: The microstructure characteristic and the major elements analysis of the fly ash from the municipal solid waste incinerators (MSWI) was conducted by using scanning electron microscope (SEM) and X-ray energy dispersive microanalysis (EDX). The results show that the shape of fly ash particles is various. Most particles are irregular, some are baculiform and very few particles are spherical and flocculent. It is found that the spherical particles contain little heavy metal, but there are a number of heavy metals on the surface of irregular and flocculent particles. On the surface and in the inner of the fly ash particles, the major elements are Si, Ca and Al as well as heavy metals such as lead and copper. At some micro-areas/points the weight percentage of lead and copper reaches 16.22% and 14.48%, relatively.
Abstract: In order to develop a low emission municipal solid waste (MSW) fluidized-bed gasification and swirl-flow melting process, a fluidized bed gasifier was designed at the laboratory scale to research the gasification characteristics of PVC, which is widely existed in MSW and brings severe pollution and corrosion in MSW thermal disposal, especially the corrosion by HCl. The experiments were carried out at different excessive air ratios (0.2~0.8) and temperatures (400 ℃~700 ℃). The products from PVC gasification were characterized by using the proximate and ultimate analyzer, gas chromatography analyzer and titration of AgNO3. When the temperature is over 600 ℃ and the excessive air ratio is about 0.4, the conversion of Cl to HCl achieves over 95%. While the gasification efficiency reaches 22%~25% and the LHV of product gas is only 2 000 kJ/m3~2 300 kJ/m3. Increasing the temperature or excessive air ratio is an effective way to reduce the yield of smoke. When the temperature is 700 ℃ and the excess air ratio is 0.6, the yield of smoke is decreased to about 10%. Based on the results of experiments, the forming mechanisms of HCl and smoke are proposed and explained.
Abstract: The granules of waste tire were pyrolysed under vacuum condition in the temperature range of 450 ℃～600 ℃, and the effects of the temperature and basic additives of Na2CO3 and NaOH were studied. The results show that the pyrolytic oil yields reach the maximum of about 48% at 550 ℃ under vacuum condition without additive. 3% NaOH could facilitate the pyrolysis reaction markedly with the maximum oil yield of 49.66% at 480 ℃ and then decrease with increasing temperature. However, the effect is little on pyrolysis of tires when 3% Na2CO3 is added. Tire pyrolysis gas, determined by gas chromatography with TCD and FID detectors, is mainly H2, CO, CH4, CO2, C2H4 and C2H6, etc. Relative content of H2 in the pyrolysis gas increases obviously in the presence of NaOH, more than 60%, but those of CH4, CO and C2 decrease. The composition of gaseous product also varies with temperature. Pyrolytic oil fractions was distilled to recover the pyrolytic naphtha (i.b.p～205 ℃). Qualitative and quantitative analysis of the pyrolytic naphtha were carried out by GC and GC-MS. It is illustrated that dl-limonene is the main component, with more than 11% concentration of the pyrolytic oil which is a chemical product with high economic value and wide industrial applications.
Abstract: Global kinetics for hydrogen production by oxidative steam reforming of methanol over Zn-Cr/CeO2-ZrO2 catalyst was studied in a BSD-2A gradient-less reactor. The experimental conditions were chosen in the range of temperature 400 ℃～460 ℃, volume space velocity600 h－1~1 600 h－1, O2/CH3OH=0.1~0.25,H2O/CH3OH=1.0~1.8. Experiments were carried out by means of L16 (45) orthogonal design. Steam reforming of methanol, methanol decomposition and methanol total oxidation are treated as independent reactions. A power-type rate model was established, in which the rate of three independent reactions are related with the partial pressure of the reactants and products. Parameters of model were determined by the linear least-square parameter estimation method. The accuracy of the experimental data and kinetics model was proved by F-examination, which fit experimental data well. The activation energy of this study is similar to the models of the literatures. Remarkably, the kinetics of the difficult reaction -methanol total oxidation is also studied and the result is feasible. These kinetics results could then be used for the design and optimization of monolith reactor for hydrogen production.
Abstract: The thermal decomposition of hydrogen sulfide to generate hydrogen is a novel control approach for hydrogen sulfide pollution. In this work, the kinetic of thermal decomposition of hydrogen sulfide was investigated. The decomposition efficiency of hydrogen sulfide under various temperature and residual time was studied by using thermodynamics analysis and experiments. The results show that the reacting mechanism proposed fits the thermal decomposition reaction of hydrogen sulfide well. The thermal decomposition of hydrogen sulfide greatly relies on the reacting temperature, and under higher temperature conditions the higher hydrogen generating efficiency can be achieved. When the temperature is low, the reaction time is the key factor to influence the thermal decomposition. The initial hydrogen sulfide concentration has a great influence on the thermal decomposition efficiency, and lower hydrogen sulfide concentration results in a higher thermal decomposition efficiency.
Abstract: The Cu-Zr-Ce-O mixed oxide catalysts for the selective CO oxidation with various ZrO2 contents were prepared by co-precipitation method and characterized by DSC/TG, XRD and TEM techniques. The effects of ZrO2 loading and different regeneration methods on the activity of Cu-Zr-Ce-O catalysts were investigated. The results showed that higher CO conversion (>99%) and selectivity in a wide temperature range（160 ℃～200 ℃） are obtained when appropriate quantity of ZrO2 is added to Cu1Ce9Oδ. The optimum composition of the catalyst is Cu1Zr1Ce9Oδ. The addition of ZrO2 can improve the thermal stability of the catalyst, decrease the pore size and change the particles' sintering manner simultaneously. The deactivated Cu1Zr1Ce9Oδ catalyst can be refreshed to certain extent by treating at 300 ℃ in nitrogen or 20％H2/N2 atmosphere, while it can be well regenerated in 20％O2/N2 at the same temperature, probably because that the treatment of 20％O2/N2 can enhance the surface absorbed oxygen and well restore the activity of the deactivated catalyst.
Abstract: Deactivated causes of Ni/AC catalyst for vapor phase carbonylation of methanol were investigated. The carbonylation reaction was carried out in a fixed bed reactor at pressurized condition in the presence of methyl iodide as the promoter. Several characterization techniques (XRD, XPS and ICP) were used to study catalyst change before and after reaction. The characterization results showed that the number of Ni0 active center decreased with the formation of NiI2, and that carbonylation active center Ni migrated continuously and accumulated on the surface of the catalyst forming the active center of carbon deposition, resulting in catalyst deactivation. Species and structure of carbon deposition on the catalyst were also investigated. Results showed that graphite carbon deposited on Ni/AC catalyst after reaction. The loss of Ni on the surface of support induced by the formation of Ni(CO)4 was confirmed by ICP-AES.
Abstract: Photocatalytic reaction for synthesizing methacrolein from C3H8 and CO2 on semiconductors has a great significance in utilization of alkanes and protection of environment. Solid material of metal-decorated coupled semiconductors Cu/V2O5-TiO2/SiO2, prepared by chemical modification method and the isovolumetric impregnation method, was introduced into photo-stimulated surface reaction (PSSR) process to synthesize methacrolein from propane and carbon dioxide. BET, XRD, TEM， IR, Raman and UV-VIS DRS techniques were used to characterize the surface structure, photon absorbing and chemisorbing ability of the material. It was shown that the active species of the photocatalyst Cu/V2O5-TiO2/SiO2, are dispersed well on the surface of the support: the extremely small particles of V2O5, and TiO2 crystallites exist on the surface of SiO2, while the metal Cu is then highly dispersed in the surface of these semiconductors. Another distinct characterization of these materials on their surface structures is that the semiconductor V2O5 is coupled with TiO2 by V—O—Ti bonds. They also form the chemical bonds with silica, which increase the combination of active species and the support. In addition, there exist abundant active sites on the surfaces of the three photocatalysts such as metallic site Cu, Lewis acid sites Tin+ or Vn+ and Lewis base sites M=O or V—O—Ti. The modification to metal Cu is helpful to expend the light-responding scope of the material, which also can improve the photo absorbing ability of the whole reaction. The active chemisorbing of CO2 and propane on the catalyst greatly promotes the photochemical synthesis of methactolein, even in low temperature. Based on the experiments, the mechanism of photo-stimulated surface reaction for synthesizing methacrolein from C3H8 and CO2 on Cu/V2O5-TiO2/SiO2 was proposed.
Abstract: We have studied a series of CoMo hydrodesulfurization(HDS) catalysts supported on TiO2-Al2O3 composite oxide and Al2O3. The difference of these catalysts was investigated by TPR(Temperature Programmed Reduction), FT-Raman, and HRTEM (High Resolution Transmission Electron Microscopy) techniques. The HDS tests were performed in a high pressure fixed bed micro-reactor with 4,6-DMDBT(4,6-Dimethyldibenzothiophene) as a probe molecule. TPR spectra results indicated that the interaction between MoO3 and TiO2-Al2O3 composite support was weaker than MoO3 and Al2O3 support, which resulted in more octahedral Mo species (MoⅥ) forming on the surface of support. Raman spectra showed that the existence of TiO2 in TiO2-Al2O3 composite support made the highest band of MoOx species shift from 958 cm-1 in MoO3/ Al2O3 to 965 cm-1 in MoO3/ TiO2-Al2O3. The blue-shift of this band which was attributed to terminal Mo=O of Mo7O6－24 implicated that the degree of aggregation of polymeric molybdenum-oxide units had increased. HRTEM graphs showed there were more multilayer MoS2 clusters in catalyst supported on TiO2-Al2O3 composite support. And multilayer MoS2 clusters were considered to be more active in HDS. The HDS tests of 4,6-DMDBT showed that the catalyst supported on TiO2-Al2O3 had higher activity than on Al2O3.
Abstract: H2-TPR, NH3-TPD, pulse adsorption of hydrogen and H2-O2 titration were employed to analyze and correlate the platinum dispersity on Pt/SAPO-11 catalyst with preparation of the catalyst and performance of skeletal isomerization of n-C12 alkane. It was found that the precursor of metal amine complex and maceration with low metal concentration and multiple maceration are favored to improve the dispersity of platinum on catalyst. The introduction of additives of Mn2+, Sm3+ and Zn2+ and binary metal maceration are feasible to promote the dispersity of metal. In addition, matching of the acidity and metal content is optimum to catalytic performance of Pt/SAPO-11 catalyst.
Abstract: Na2CO3-NaOH was used as precipitator to prepare Ba modified Ni/γ- Al2O3 catalysts with co-deposition method. XRD and BET showed that the catalyst prepared by this method had better dispersion of the active components and strong interaction between the active component and the support. Compared with Ni/γ- Al2O3 catalysts, the addition of Ba enhanced the activity and the stability of the catalysts for partial oxidation of methane. The CH4 conversion was close to 100% and H2 selectivity reached 98.1% over Ba modified Ni/γ- Al2O3 catalysts under the condition of space velocity=80 000 h－1 and CH4/O2/N2=14/7/79 at 800 ℃. The addition of Ba did not change the BET area of the catalysts, but inhibited the formation of granular NiAl2O4, which favored the existence of activity component, and improved the stability of the support so as to improve the catalyst performance. After 15 h stability test at 800 ℃, the methane conversion was kept about 95%. The test results show that Ba modified Ni/γ- Al2O3 catalyst has higher activity for partial oxidation of methane.
Abstract: Methane conversion to C2 hydrocarbons by low temperature plasma was studied in different reactors. The results showed that the product distribution varies with the change of the reactor type. In the reactor A and B, products contained more acetylene and less amount of ethylene and ethane, while in the reactor C and D, the main products were ethane and propane with little amount of ethylene and acetylene. The coke deposited on electrode had a high influence on methane conversion in reactor A, and a little effect on reactor C. The coke deposition conversed to CH4 via pure H2 discharge in those reactors. Through the products distribution, the reaction mechanism was deduced in different reactors. In reactor A and B, because of the high electron energy and density, methane was mainly decomposed to atom C and then it combined with itself or atom H to form C2 and CH, which directly formed the main product C2H2. In reactor C and D, methane was mainly decomposed to CH3 for the low electron energy and density and then CH3 combined with CH2 or itself to form C2H5, which were the precursor of C2H6. And the main byproduct, C3H8, was formed by coupling of C2H5 and CH3.
Abstract: The catalytic combustion of low concentration methane was systematically investigated in a pilot scale reverse flow reactor. The influences of cyclic period, the concentration of reactant and the space velocity on the operation performance of reactor were studied. The experimental results showed that, for the reverse flow reactor, cyclic period, the concentration of reactant and the space velocity were three important operation parameters that obviously affected the axial temperature profiles of reactor. It′s possible to maintain autothermal operation with high conversion of methane even though the methane concentration decreased to 0.5%. When the methane concentration was increased up to 0.8%, the highest temperature of catalyst bed was beyond 700 ℃. It suggests that the energy of the hot gas should be recovered and this reactive technology is able to be used in power production with low concentration methane.
Abstract: The trace elements emission could result in harmness to the environment and human health during coal combustion. The removal of trace elements before coal combustion is an effective method. The transformation and removal behavior of arsenic in Wujiaping (WJP) coal during sub-critical water treatment was studied in a semi-continuous apparatus. Effects of temperature, pressure, residence time and water flow rate on the arsenic removal were discussed. The occurrence modes of arsenic in WJP raw coal and residuals treated by sub-critical water were also studied by float-sink experiments and sequential chemical extractions. The results show that with the increasing of temperature, pressure, residence time and water flow rate, the arsenic removal in WJP coal also increases; and at the condition of 380 ℃, 15 MPa, 60 min and water flow rate of 0.58 L/h, the arsenic removal is about 62%. Arsenic in WJP coal mainly is associated with sulfates & mono sulfides, disulfide & some organic matters and “insoluble forms”. Sub-critical water treatment can decrease all these arsenic forms in coal and transfer them into the volatile form.
Abstract: The high sulfur coal Hunan Meitanba was used as the experiment sample. The carbide slag was added based on the Ca/S mol ratio of 1.5. K2CＯ3, Al2O3, Fe2O3 and rare earth minerals ( weight of rare earth oxides above 58%) about 1.0% were added in the coal respectively. The promotion effects of the additives and catalytic mechanism on carbide slag sulfur capture were studied. The results show that 4 additives have good promotion effects on sulfur capture by carbide slag between 800 ℃ and 1 100 ℃. Adding K2CＯ3 has the best sulfur capture result at about 1 100 ℃. Decomposition temperature of carbide slag and utilization efficiency of Ca are improved to increase sulfur capture ratio when Al2O3 is added. Fe2O3 has a good effect on sulfur capture, and the effect weakens with increasing temperature. Rare earth element has particular electronic shell structure which makes especial catalysis impact on sulfur capture. Al2O3 is the best among the 4 additives and it makes sulfur capture ratio reach above 70%, and rare earth minerals is the second.
Abstract: In order to develop a new process of low-temperatutre methanol synthesis, reaction performance of the low-temperature methanol synthesis catalyst CuCr/CH3ONa was examined in the bubble column slurry reactor (BCSR)of 40 mm in diameter and 4 500 mm height. The slurry was composed of the required amounts of sodium methoxide solution, CuCr catalyst and emulsifier OP-10, as well as the balanced liquid xylene medium. The results showed that the average conversion of CO was 78% in 90 ℃~110 ℃, 4.8 MPa and operation gas velocity 0.2 cm/s during first 9 h of operation test. Methanol was main product from BCSR. Compared with the results of the test in the autoclave, efficiency of BCSR is about 80% of the autoclave reactor’s. This is probably due to the consumption of CH3ONa and the negative effect of emulsifier OP-10. Results demonstrated the feasibility of the application of BCSR in low temperature methanol synthesis in slurry.
Supervisor：Chinese Academy of Sciences
Sponsors by：Shanxi Institute of Coal Chemistry, Chinese Academy of Sciences Chinese Chemical Society
