Abstract: Entrapped hydrocarbons from asphaltene and products from the ruthenium ions catalyzed oxidation (RICO) of asphaltene were used to study the biodegraded crude oil. The results indicate that the biomarkers, which are almost destroyed by biodegradation in the oil, can be recoveried from asphaltene by these two methods. A fairly intergrate series of hopanes and steranes are discovered in the entrapped hydrocarbons, and a homologous series of hopanoic and steranoic acids are also detected in the RICO products. Compared with other methods, these methods are simple and convenient, and the results obtained are credible and accurate. Hence, these new methods are significant for the study of biodegraded crude oil.
Abstract: The pyridine adsorption and swelling behaviors of WK11 model compound, ND and IL coals in pyridine containing water, cyclohexane and toluene binary solvent mixtures were investigated. The results suggested that the pyridine adsorption amount and swelling ratio were very low when a small amount of pyridine existed in solutions. The small amount of pyridine could not be totally adsorbed by coal even after very long experiment time. Although pyridine could break all hydrogen bonds in coal due to the more favorable entropy change, other factors including environmental surrounding solvent, pore structure of absorbent and molecular diameter of absorbate could influence the adsorption behaviors greatly. The coal swelling ratio also did not have linear relationship with the uptake of pyridine in low concentration stage. At high pyridine concentration, the swelling ratio increased with the pyridine concentration. However, the boundary between coal particles and solvents would disappear when the pyridine concentration was high enough.
Abstract: The micrometer scale spherical Fe-Cu-K-SiO2 catalysts were prepared by means of spray drying technology for precipitate slurry, which was obtained by a continuous precipitation method using four inexpensive industrial by products, FeSO4 as raw material. The reactivity, selectivity and stability of four catalysts for Fischer-Tropsch synthesis were tested in a fixed-bed reactor at 526 K, 2.0 MPa and gas hourly space velocity of 2 000 h－1 with syngas of H2/CO=2 during the period of 240 h. The results indicated that four catalysts showed higher CO conversion and C5+ product selectivity, the CO conversion gradually decreased with differentrates. In terms of the CO conversion and stability, catalyst 2# was the best among the catalysts studied. Its initial CO conversion was 77.89%, and passed through a maximum of 89.58% after an inductive period for about 40 hour, and then gradually decreased with a deactivation rate of 1.33%/d. The selectivity of CH4 and C5+ kept about 4% and 80%, respectively, in the whole run period for catalyst 2#.
Abstract: The primary fragment phenomenon of coal during combustion was introduced and one dimension model of single particle coal was established. The results indicate that the primary fragment of coal during combustion results from the accumulation of coal volatile, which leads to the production of pressure gradient in coal. This explains well the pulverization phenomenon of coal. The particle size distribution based on the primary fragment inside the combustion chamber could be predicted in the future. In the meantime, the effect of primary fragment of coal on design and operation of circulating fluidized bed combustion boiler was also demonstrated.
Abstract: Catalysts prepared by different approaches show different properties and different catalytic performance. The effects of precursor metal, content of precursor metal, preparing method as well as SnO2 content on the catalytic activity and stability of methane combustion were investigated. Sol-gel method involving supercritical fluid drying technique was employed for the preparation of ZrO2-based materials. Activity evaluation of methane combustion was executed. The results indicated that NiO/SnO2-ZrO2 was a kind of proper catalyst in methane combustion, and most of catalysts led to the full conversion of methane at about 700 ℃ without the production of CO. NiO content is the most important preparation parameter for activity and thermal stability of catalyst, but NiO content influenced the activity and thermal stability of catalysts in an opposite way. X-ray diffraction(XRD) revealed Sn might be advantage of the high temperature stability of ZrO2 powder.
Abstract: Chlorine is one of trace elements in coal, which do harm to environment badly. It is of significance for the removal and control of chlorine in coal that the isolation characteristic of chlorine in coal was studied. In this paper, test data were fitted by using Boltzmann function, and model of chlorine removal was built on the process of coal pyrolysis. Relative error between model data and test data was low t10, t50, and t90 were put forward to compare to the temperature at which chlorine removal was 10w%, 50w% and 90w% respectivelyΔt80 was used to describe the primary temperature range of chlorine removal during pyrolysis. On the basis of these, the experimental data showed that the pyrolysis temperature of coal was different when the chlorine removal changed from 10% to 90%. Chlorine removal from coal was above 90w% at the pyrolysis temperature of 900 ℃.
Abstract: The mode of occurrence of trace element in coal is an important factor that influences the evolution behaviour of the element during coal conversion. In this paper, the mode of occurrence of As, Pb, Cd, Cr in Yima coal was determined using various methods including density fractionation, demineralisation and sequential chemical extraction. The results by different methods were roughly identical. Arsenic in Yima coal was found to be primarily associated with pyrite. Part of Cadmium associated with pyrite, while others with other mineral matters. Lead in Yima coal might be dispersed in many mineral matters such as sulfates, sulfides, silicates and carbonates. The mode of occurrence of Chromium was much different from other three, it was primarily associated with organic matters in Yima coal.
Abstract: This investigation involved the formation and release of precursors of NOx，which are HCN and NH3, during coal and its char gasification. Gasification was carried out in a fixed bed reactor at atmospheric atmosphere. Gasification agents and gasified temperature were two key effects on the release amount of nitrogenous compounds. Results show that with an increase of reaction temperature a great amount of NH3 is formed during gasification of coal and its char with steam; the yield of NH3 is highest at 800 ℃ during gasification of coal and its char with CO2; the volatiles in coal plays the key role in the formation of HCN and NH3 during coal gasification under steam atmosphere; the yield of HCN during coal gasification is independent of gasification agents and increases with an increase in gasified temperature.
Abstract: A new set of reduced global mechanism with NOx formation has been developed for methane oxidation from the detailed mechanism GRI2-11 using a computer algorithm for automatic generation of reduced chemistry, after selecting the non-steady-state species. The global mechanism, consisting of 18 species and 14 lumped reaction steps, is based on the sensitivity analysis and the quasi-steady-state approximation. The 14-step reduced mechanism is then used in perfectly stirred reactor and laminar premixed flame, the results show that it exhibits good to excellent performance in predicting a wide range of combustion phenomena and the formation of NO under extensive thermodynamic parametric variations, compared with the results of the detailed mechanism GRI2.11.
Abstract: Six nature minerals (Acidic argil, Alumina, Kaolinite, Extra grade kaolinite, Meerschaum and Diatomaceous earth) were selected to remove NaCl vapor at high temperature. Main elements of these natural minerals are Si and Al. Experiments were carried out in a self-made equipment which mainly consists of NaCl vapor generating section, fixed-bed reactor and gas absorption section. Results showed that sodium content is dependent on chemical constituent and microporous structure of sorbent and sodium content (4.65%) of kaolinite is the highest in the condition of 850 ℃, 11.0 m/h gas velocity and 5 h operating time. Effects of temperature and gas velocity on sodium content of kaolinite were discussed. Results showed that there is an optimal temperature around 875 ℃ for kaolinite to remove NaCl vapor and sodium content increases when space velocity decreases. In addition, adsorption process of NaCl vapor on kaolinite at 850 ℃ and 11.0 m/h gas velocity was found to be influenced by both chemical reaction and diffusion of a sodium resultant layer from the kinetics.
Abstract: The reaction process of quickly liquefying Chinese Yangcun bituminous coal was studied under pressure of hydrogen 7.0 MPa(cold) by using resonance agitation reactor. The results show that a high coal conversion has been obtained at short reaction time (coal quick liquefaction) by raising reaction temperature appropriately and enhancing active hydrogen concentration and improving its transfer speed and path in the reaction system. The best reaction temperature of coal quick liquefaction (CQL) is the upper limit of the coal pyrolysis temperature range in TGA. Compared coal conversion and benzene soluble (BS) yield of CQL with those of common liquefaction，CQL greatly enhances efficiency of coal liquefaction and it is favorable for further utilizing coal liquefaction product.
Abstract: The effect of steam content and reaction temperature on the catalytic conversion of Naphthalene, which was chosen as the model compound in pyrolysis gas from biomass, has been investigated with a Ni-Pt/Al2O3 catalyst in a fixed bed reactor. It has been confirmed that increasing the reaction temperature not only enhances the conversion of naphthalene and H2-, CO-yield, but also improves the CO-selectivity, however the H2-selectivity and the carbon deposit decrease. High steam content is favorable to increase the naphthalene conversion, the H2-yield and -selectivity, but the CO-yield and -selectivity as well as the carbon deposit decrease with increasing steam content. It is also found that the concentration of benzene, a by-product of naphthalene conversion, increases with the enhanced steam content and reaches a maximum at 700 ℃.
Abstract: The coke deposition of various aromatics on hydrocracking catalyst has been obtained using accelerated aging experiment. Acid strength distribution, pore structure and coke type of catalyst were measured by FT-IR,physical absorpmeter and thermal analysis. The results showed that for single ring aromatics, involving benzene, toluene, para-xylene, ethylbenzene and styrene, the characters of substituted-groups, including carbon chain length, number and saturation, could affect the amount of coke and pore character. Longer carbon chain, larger number and less saturation could result in more coke deposition on catalyst. For different rings aromatics without any substituted-group, involving benzene, naphthalene and phenanthrene, the amount of both general coke and the pseudo-graphite structure coke increase with the increase of aromatic rings, but the total amount of acid decreases gradually, especially for strong acid. For all aromatics, the specific surface area of deactivated catalyst decreases with the increase of the coke. The coke impenetrates in all pores and mainly deposited in small pore of catalyst, while some of coke could form mechanical pore on catalyst surface.
Abstract: Co-Mo based catalysts can be widely used in petrochemical, coal based chemical and fertilizer industries. Recently, many excellent Co-Mo based commercial catalysts have been exploited out by means of Preparation-process innovation, active components and/or additives adjustments and new type of support introduction. In this paper, the features of Co-Mo based sulfur-tolerant CO shift catalyst are characterized by using of Micro-Reactor, Temperature-Programmed Reduction (TPR), Temperature-Programmed Sulfurization (TPS) and in-situ IR techniques. It is found that there are two kinds of active sites on the Cu-Mn/Al2O3 catalysts, one is Cu or Mn, and the other one is formed via their interaction. The catalytic activity is contributed to both of the two kinds of the active sites.
Abstract: Dibenzothiophene(DBT) can disperse spontaneously on the surface of MoO3/γ-Al2O3 catalyst under 80 ℃ and 24 h. It is determined by XRD that the dispersion threshold of DBT on MoO3/γ-Al2O3 catalyst is 0.23 g/g. This value is obviously higher than the calculated value of monolayer dispersion of DBT assuming that DBT adsorbed flatly on the surface of MoO3/γ-Al2O3 catalyst. It is inferred from this result that the adsorption of DBT on the surface of MoO3/γ-Al2O3 catalyst may include both two status, one is the end-on manner through the adsorption of sulfur atom, another is the flat manner through the adsorption of π electrons of DBT molecule. The result of FT-IR analysis does not contradict with the inference. DBT may be adsorption on the acidic sites in the surface of MoO3/γ-Al2O3 catalyst via sulfur atom.
Abstract: The effect of reduced K-Co-Mo catalysts made by sol-gel methods on the performance for mixed alcohol synthesis is investigated. The results reveal that the addition of promoter potassium and cobalt enhances the alcohol production remarkably, especially the selectivity to C2+-alcohol. In addition, the catalytic properties are obviously influenced by reaction conditions. Increasing the reaction temperature improves the space-time-yield(STY) of alcohol, but decreases the selectivity to alcohol while raising the pressure or the space velocity are in favor of the alcohol synthesis. Under the conditions of 230 ℃，6.0 MPa，14 400 h－1, over the reduced K-Co-Mo ultra-fine catalyst, the STY and selectivity of mixed alcohol are 375.4 g/kg·h and 70.2%,respectively, and the ratio of C1OH to C2+-OH is only 0.48.
Abstract: The relationship of TS-1 activity with time was investigated in a continuous epoxidation reactor, and the function curve of time to TS-1 activity was observed. The used catalyst was regenerated by calcinations.The results of the activity tests indicated that the activity of the regenerated catalyst was almost recovered.The fresh, the deactivated and the regenerated were characterized by a number of techniques such as SEM, N2 physical adsorption, TG, XRD, IR and NH3-PD.On the basis of the characterization, the mechanism of the deactivation was proposed.The deactivation of TS-1 can be attributed to the deposition of slowly diffusing organic by-products inside TS-1 channels. Additionally, small amount of titanium may be leached out from the framework of the catalyst.
Abstract: A series of alkaline- or/and alkaline-earth-promoted, carbon-supported ruthenium catalysts have been prepared N2 physisorption, CO chemisorption and X-ray diffraction were carried out to investigate the effect of promoter on the surface area, pore size distribution and ruthenium dispersion of catalysts. The activities of the series catalyst for ammonia synthesis were measured under the reaction condition 430 ℃, 10.0 MPa and 10 000 h－1. It has been found that the effectiveness of alkaline- or alkaline-earth-promoter is roughly related to the basicity of alkaline metal hydroxide or alkaline-earth metal oxide. For the single-promoted Ru/C catalyst, cesium and barium proved to be most effective in the alkaline and alkaline-earth promoter. Barium-promoted Ru/C catalyst was more effective in ammonia synthesis than cesium-promoted Ru/C catalyst. Barium was suggested to have a stronger interaction with the Ru surface than cesium. For the double-promoted Ru/C catalyst, the activity of the catalyst was affected remarkably by the method of preparation. Barium and cesium promoter in 4w% Ru-Ba-Cs/C were impregnated by two steps method, barium was impregnated first, after reducing treatment at 400 ℃, cesium was impregnated again. The catalyst of 4w% Ru-Cs-Ba/C was prepared from impregnating cesium first barium later by two step impregnation. The catalyst of 4w% Ru-(Ba+Cs)/C was prepared from co-impregnation the mix aqueous solution of barium and cesium by one step method. The result showed that the activity of 4w% Ru-Ba-Cs/C was higher obviously not only than 4w% Ru-(Ba+Cs)/C, but also than 4w% Ru-Cs-Ba/C. Because barium and cesium competed adsorption during the process of preparing the double-promoted Ru/C catalyst, that would influence the surface distribution of barium and cesium promoter and ammonia synthesis activity of the Ru/C catalyst.
Abstract: There are two stages in the overall CaO Sulfation process: The initial stage of sulfation is chemical reaction control and its speed is faster. The second stage reaction proceeds under the product-layer-diffusion control regime after CaSO4 buildup. The later rate of sulfation is slower. It is very important how to improve the rate of the second stage of sulfation. The major process is that Ca2+ ions outward diffuse through the sulfate product layer to the surface of CaSO4 and react with O2－, O2 and SO2 other than they move inward to react with CaO covered by CaSO4, when the solid product layer CaSO4 of sulfation reaction is dense and not cracked. The CaSO4 covering and the pores in the CaO particles being plugged resist the further sulfation reaction. Hence, how to increase the rate of the further sulfation reaction is largely investigated. Several kinds of experiment technologies are performed to identify the mechanism of the Ca2+ diffusion. And a new mechanism greatly supports the result that the additives can obviously increase the overall conversion of CaO.
Supervisor：Chinese Academy of Sciences
Sponsors by：Shanxi Institute of Coal Chemistry, Chinese Academy of Sciences Chinese Chemical Society
