Abstract: Vitrinite and inertinite separated from Shenmu coal using sink-float method combined with hand-picking were systematically investigated by ultimate analysis, FT-IR,13CNMR and TG/DTG. The results showed that the optimum density for separation of vitrinite and inertinite from Shenmu coal was 1.320 g/cm3～1.324 g/cm3 and 1.378 g/cm3～1.382 g/cm3 respectively. The purity of vitrinite and inertinite was 97.55% and 96.90% at this separation condition. Vitrinite had higher hydrogen content, lower aromaticity of 0.51 and a large amount of hydrogen bonds, while inertinite had higher carbon content and aromaticity of 0.76, and those of parent coal was in the middle of them with aromaticity of 0.68. The result of FTIR showed that at the same temperature vitrinite had more hydrogen bonds, higher aliphatic hydrogen content and lower Har/Hal ratio. With increasing temperature, the content of aromatic hydrogen and Har/Hal ratio all increased and the aliphatic hydrogen decreased. The result of TG/DTG showed that vitrinite had higher thermal stability than inertinite and the remaining volatile matter in vitrinite was lower than that in inertinite at the same Har/Hal ratio, which was consistent with the fact that inertinite had higher aromaticity and lower aliphatic hydrogen content and suggested that the chemical property of maceral affected its reactivity.
Abstract: Using a batch autoclave，preliminary study was made on the reaction of coal tar in supercritical water. Attention was centered on the influence of temperature, residence time and density of water on both composition and yield of products. Experiments were performed between 390 ℃～480 ℃, solvent density 0.32 g/cm3～0.44 g/cm3, and reaction time up to 80 min. Compared with the traditional pyrolysis of coal tar under normal pressure or high pressure, it is found that during the upgrading of coal tar in SCW, light oil is increased at the expense of gas and coke products, probably due to the cage effect of SCW in the pyrolysis of coal tar. SCW may be an ideal medium for upgrading of coal tar and can suppress gas formation and coking of coal tar. In order to get light oil as much as possible, the optimal conditions are: temperature 450 ℃, density of water 0.40 g/cm3 and residence time 20 min. The yield of light oil (HS) is 51.55w% under these conditions, 30％ higher compared with that in the raw material.
Abstract: It is important to understand the existing forms of organonitrogen compounds in coal and subsequently to choose proper approaches for removing and utilizing the components. The tetrahydrofuran/methanol-insoluble fraction (residue) was obtained by solvent extraction from Datong bituminous coal, then noncatalytic and metal (Fe, Ni and Pd/C)-catalyzed thermolysis of the residues were conducted in cyclohexane under pressurized hydrogen at 300 ℃. Petroleum ether-soluble fractions from thermolysis products were identified with GC/MS. The results showed that organonitrogen can be released from the residues in metal (especially Ni and Pd/C)catalyzed thermolysis. The detected compounds are predominantly aniline and its alkylsubstituted derivatives. The metal-catalyzed hydrogenation of polycyclic aromatic rings in coal destroyed both intermolecular interactions and covalent bonds so that the organonitrogen compounds could be released from macromolecule network.
Abstract: This paper presents a novel method for detection of asphaltene precipitation in residues, which is based on measurement of the electrical conductivity of the residua solution as a function of added precipitant, n-heptane. The maximum of the mass fraction normalized conductivity of the solution is found to be the beginning point of asphaltene precipitating. Then the ratio of n-heptane to residue when the maximum of the mass fraction normalized conductivity of the solution gained can be defined as the indication of the stability of residue. Four kinds of sample are studied by this method. DaQing VR and the maltene of Middle East VR are the most stable because they contain little n-C7 asphaltene. Middle East VR is more stable than Middle East AR for it contains less saturate. The result is consistent with the characteristics reflected from the saturate, aromatic, resin and asphaltene constitutes of them.
Abstract: Mn/Ni/K/MoS2 catalysts prepared by different methods and their performances for higher alcohols synthesis from syngas were tested under different reaction conditions. The C2+ alcohols content, the selectivity and space-time-yield of alcohols obviously increased when the catalyst with Mn content of only 0.26% was prepared by co-precipitation using (NH4)2MoS4, Mn(AC)2·4H2O and Ni(AC)2·4H2O as the precursors. As the content of Mn in Mn/Ni/K/MoS2 catalyst prepared by successive precipitation increased to 0.66%, the space-time-yield was improved remarkably. The effect of Mn content on catalytic performance was then investigated over Mn/Ni/K/MoS2 catalysts prepared by impregnation method. The results showed that the selectivity and space-time-yield of alcohols reached the maximum, i.e. 69.6% and 0.338 g/mL·h at the reaction conditions of 315 ℃, 9.5 MPa and 6 000 h－1 when the Mn/Mo (molar ratio) was 1.5. Furthermore, the stability test for 300 h over Mn/Ni/K/MoS2 catalyst prepared by co-precipitation showed that the catalyst had a good stability.
Abstract: The catalysis of copper complexes bearing ligands of imidazole and derivative compounds is systematically studied in the reaction of oxidative carbonylation of methanol to dimethyl carbonate. The best multifunctional promoter N-methylimidazole，which has better performance on solubility, inhibition of corrosion and promoting catalysis for oxidative carbonylation has been found. The experiments show that cuprous chloride could be solved completely after adding N-methylimidazole to liquid methanol. It will be very useful in the application of this new catalytic system in production of dimethyl carbonate. The molar conversion of methanol and selectivity of dimethyl carbonate was 15.4x% and 98s%. respectively when the reaction was carried out under 120 ℃, 2.4 MPa, pCO/pO2=2∶1, CCuCl=0.2 mol/L,CNMI/CCuCl=4∶1, and reaction time 3 h. The corrosion experiment was carried out in CuCl/NMI /CH3OH/H2O liquid system at 50 ℃ and 0.1 MPa of CO/O2(molar ratio 2∶1) reaction gas atmosphere.The corrosion rate of Q235 steel in the reaction system is 0.22 mm/a and the inhibition efficiency is about 94.5%. The kinetic study shows that the reaction is almost first order for the N-methylimidazole/CuCl catalytic system, and the rate constant is about 0.15 min－1.
Abstract: To study the effect of rare earth chloride on vapor phase carbonylation of methanol to acetic acid, a series of catalysts (Ni-La/AC) were prepared by loading LaCl3 onto Ni-based catalysts. The catalysts were characterized by means of BET, XRD and TPR, then were applied to the methanol carbonylation reaction after being heat treatment in nitrogen at 400 ℃ and reduction by hydrogen at 550 ℃. It was revealed that under pressurized conditions in the presence of methyl iodide, these catalysts had positire effects on induction period, conversion of methanol and yield of carbonyl products. The results indicated that Ni（5%）- La (3.8%)/AC had better catalytic activity. Compared with Ni（5%）/AC at the same operation conditions, the conversion of methanol is increased by 11.52% and the total yield of carbonyl products is improved by 12.16%.
Abstract: The primary products formation during cellulose pyrolysis was studied using a heat radiation reactor. Combined with GC-MS analysis, Levoglucosan (LG) appeared to be the most important component, and its proportion in bio-oil was about 45w%～85w%. LG was mainly formed at 550 ℃～650 ℃ for the medial temperature of thermal radiation source (TRS). There existed an optimum TRS temperature about 640 ℃ for LG production. Glycolaldehyde and acetol were also the major components, which took up about 6w%～14w% and 3.5w%～8w% in bio-oil separately. However, their production always increased with TRS temperature within a rather wide range, showing that high reaction temperature benefited their formation. Furthermore, glycolaldehyde and acetol were formed in primary reaction competing against LG formation during cellulose pyrolysis, rather than formed from secondary cracking of LG.
Abstract: The thermal degradation of PP/PVC mixture at 380 ℃ was carried out in a glass batch reactor under atmospheric pressure. The boiling-point (bp) distributions of degradation products and its chlorine removal were examined. The catalytic thermal degradation of the plastic mixture was also carried out with ZSM-5 as catalyst and iron oxides (α-FeOOH, Fe2O3, Fe3O4) as chlorine sorbents. Compared with thermal degradation, the ZSM-5 catalyst accelerated the rate of degradation, increased the weight percent of lower molecular weight component, and lowered the bp of the liquid products. As a dechlorination sorbent, α-FeOOH can significantly decrease the chlorine content in the oil from 1.65w% to 0.63w%. When α-FeOOH /ZSM-5 is used in vapor phase, the organic chlorine content can decrease to 0.13w%. Fe3O4 also possesses the ability of dechlorination. It is the crystalline structure of Fe3O4 that is very efficient for dechlorination.
Abstract: The test system includes a biomass pyrolysis reactor with rich husk as feedstock and a tar cracking reactor with dolomite as catalyst. The effects of pyrolysis temperature on the tar yield, cracking temperature and residence time on the tar conversion rate are examined. The results show that tar conversion rate increases with increasing cracking temperature and residence time. The tar conversion rate during catalytic cracking is higher than that during thermal cracking at the same temperature. The tar catalytic cracking mechanisms are analyzed by comparison of thermal and catalytic cracking results. The gas components after catalytic cracking are investigated. It shows that H2 and CH4 increase while CO2, C2H6, and C2H2＋C2H4 decrease due to the water-gas shift reaction. The results indicate that catalytic cracking of tar with dolomite is suitable for tar elimination.
Abstract: A microreactor-GC apparatus has been used for studying COS hydrolysis reaction kinetics over TGH catalyst. The intrinsic reaction kinetics of COS hydrolysis over a TGH catalyst was investigated in the temperature range of 50 ℃～7 ℃, H2O/COS molar ratio of 60～550 with the presence of CO2. Nonlinear Marquart Regression was employed to analyze the experimental data. The reaction kinetics are expressed as follows: The kinetic model can be interpreted the reaction in terms of mechanism. The presence of CO2 seems not to change rate constant and activation energy of COS hydrolysis reaction.
Abstract: Physiochemical properties and their activity, selectivity of a series of aluminum silicate catalysts for MTBE cracking to isobutene were examined by catalytivity test, XRD, physical adsorption and FT-IR. The results showed that the addition of suitable promoter and calcining at an appropriate temperature could improve the physiochemical properties and activity of the catalyst. In all properties measured in this paper, specific surface area, total acid amount and the ratio of Bronsted acid to Lewis acid could have close relations with catalystic activity. It was also found that the MTBE conversion and isobutene selectivity over the catalyst named WVI were 99.9% and 99% respectively under the conditions of atmospheric pressure, 2 h－1 and a wide temperature range from 220 ℃ to 360 ℃.
Abstract: In this paper, titanium silicate-1 (TS-1) catalyzed ring-opening of propylene oxide in process of propylene epoxidation using alcohol as solvents was studied. The ring-opening is the side reaction of epoxidation. The acidic reaction mechanism and the effect of different alcohols on ring-opening reaction were discussed in detail. Acidity mainly originates from proton acid produced by the interaction of active sites of TS-1 with H2O2. Alcohol solvents can obviously enhanced acidity. The order of three alcohol solvents according to extent promote acidty is methanol>iso-propanol>sec-butanol. With assumption of Eley-Rideal mechanism that PO molecule absorbs on the catalytic site reacts with dissociated solvent molecule, and surface reaction is the rate-controlling step, also consider absorptivity of components on the TS-1, a mechanism model was proposed. After parameter estimation, relevant kinetics equation was obtained which well fit the experimental data. The average relative deviation between experimental and calculated reaction date is less than 10%.
Abstract: The catalytic properties of well-ordered, mesoporous, hybrid SBA-15 materials founctionalized with sulfonic acid group prepared by direct-synthesis were studied. The esterification result of oleic acid with methanol showed that the SBA-15-SO3H has the highest activity among the solid acid catalysts and almost approach that of sulfuric acid. The influences of reaction temperature, ratio of acid to methanol, catalyst amount were discussed. The optimal operation conditions are that reaction temperature 60 ℃, ratio of Methanol/Oleic acid 2∶1(mol/mol), ratio of catalyst to reactant 1 g/14 g. The X-ray diffractions of fresh and reacted SBA-15-SO3H show that the samples have a very intense low-angle peak, indicating the presence of uniformly sized pores in the materials. There are also two weak peaks in the reacted sample, which meaning the mesostructure was remained. By a way, the conversion of oleic acid during three time reactions showed this catalyst has higher stability. The catalystSBA-15-SO3H can be used to replace the liquid acid for the synthesis of fat acid ester.
Abstract: The synthesis of MSU-X below pH 3 using sodium silicate solution as silica source has rarely been reported. In the present work, the range of pH value has been extended to about 0.78. Mesoporous MSU-1 silica has been readily synthesized from inexpensive sodium silicate solution and commercial non-ionic surfactant (AEO-9) by the so-called two-step method. Firstly, the inorganic precursor and nonionic surfactant solution at the metastable state (pH2～pH3, t=2 ℃) were assembled and then the silica polycondensation was induced by adjusting pH of the reaction solution (pH0.78～3.94). The products exhibit narrow pore distribution, enhanced short-range order mesoporous structure and micrometric particles- The sample prepared at pH 1.98 has the thinnest pore wall, the largest specific surface area and pore volume, while that synthesized at pH 0.78 has the thickest pore wall, the largest pore diameter and d100 value. The pore wall thickness of products decreases at first and then increases with pH increrase.
Abstract: GS, a FCC gasoline sample, was first distilled into 6 cuts, and the detailed sulfur compositions present in each cut were analyzed using an Agilent 6890 gas chromatograph configured with an G2350A atomic emission detector (GC/AED). The data show that the sulfur compounds are mainly thiophenes and alkyl-substituted thiophenes, and the distribution of sulfur is not uniform, and a large part is concentrated in the heavy cut of the sample. The data can also be used to estimate the cut point between light and heavy cuts, which is helpful to remove sulfur effectively by different methods at lowest cost.
Abstract: Datong coal was pulverized to 0.074 mm and dried at 105 ℃, then oxidized with hydrogen peroxide under mild condition. Both raw and oxidized coal were extracted with methanol/tetrahydrofuran (THF) mixed solvents under ultrasonic irradiation, then the extracts were analyzed by GC/MS so as to study the difference of extracting between raw and oxidized coal. The result indicates that the extraction yields of oxidized coal were higher than those of raw coal at the test conditions and the extraction yield increased with increasing THF concentration. The components of the four extracts were different from each other, indicating that chemical components of extracts can be changed by both oxidation and THF content in mixed solvent. But the compounds in all the four extracts were mainly hydrocarbons. In addition, coal particles were supernatant through formation of coal powder-extract-solvent colloid, therefore, filtration must be taken in coal extraction under ultrasonic irradiation.
Abstract: The combustion characteristics of the coke from the pyrolysis of asphalt have been studied using thermogravimetric analysis at atmospheric pressure. The samples were heated to the preset temperature under nitrogen which was changed into air quickly. The coke was burnout. A first-order model was established to describe combustion of the coke. In the model, the activation energy, E, is independent of the type of coke, and equal to 180 kJ/mol. The frequency factor not only depends on the coke type, but also the combustion conditions, such as temperature.
Abstract: A new low-cost apparatus used to study the character of coal combustion in place of thermograimetric analyzer was developed based on the CO2 release. In order to prove the new idea, CO2 concentration of four coal samples during ignition, combustion and burnout was measured by means of the apparatus developed by the authors. The characters of special machanism based on the relation between the temperature and CO2 concentration (t-CO2), also the derivative curve Dt-CO2 were obtained. The change of CO2 can indirectly estimate the coal combustion characters.
Abstract: Through carbonization and Fe additive with Jixi bituminous coal as a raw material, the author research on a preparation of CMS using in production of nitrogen rich air with air separation and examine. The influence of carbonization condition and Fe additive on the air separation performance of the products, the influence of carbonization conditions such as the carbonization temperature, the heating rate and the holding time as well as the additives such as coal tar, Fe3O4 and their ratio in the raw material were studied. It is concluded that Jixi bituminous coal is a good raw material for preparation of CMS. The optimum carbonization conditions are bond dosage 35w%, Fe additive (Fe3O4) 25.3w%, heating rate 10 ℃/min, final carbonization at 900 ℃ for 60 min.
Supervisor：Chinese Academy of Sciences
Sponsors by：Shanxi Institute of Coal Chemistry, Chinese Academy of Sciences Chinese Chemical Society
