03 Gaseous fuels (derived gaseous fuels)

reaction temperature, partial pressure and space velocity of di-Me ether dictate the product spectrum, ranging from lower olefins (ethylene and propylene) to gasoline-range hydrocarbons. The focus of this paper is to make a thorough study on the aforementioned details of this process and to compare its merits with those of methanol conversion.

99101967 /n-situ desuifurization during gasification of high-S coal briquettes in fixed-bed reactor at atmospheric pressure. I. influences of various factors on desuifurization Liu, Z. el al. Meitan Zhuanhua, 1997, 20, (2), 80-86. (In Chinese) In this paper, the desulfurization behaviour of limestone/dolomite and the influences of coal, three desulfurizers, additives and test conditions on sulfur capture efficiency were studied at atmospheric pressure in a fixed- bed reactor. Maximum sulfur capture efficiency reached 90.18% in the test. The results showed that (1) desulfurization of coal could be improved by increasing the size of the coal; (2) dolomite was more effective than limestone for sulfur capture; (3) the large size of desulfurizers and high Ca/ S ratio improved sulfur capture; (4) loess and alkali liquors depressed in- sifu desulfurization; and (5) the gasification temperature, time and atmosphere affected the sulfur capture efficiency.

99101968 influence of catalyst supports on partial oxidation of natural gas to synthesis gas Chu, W. et al. Tianranqi Huagong, 1998, 23, (3), 29-33. (In Chinese) The impregnation method was implemented to prepare a nickel-base catalyst for the partial oxidation of natural gas to synthesis gas. The influences of its support and active component content on its catalytic activity and physicochemical properties were investigated through experi- ments of temperature-programmed reduction (TPR) and X-ray diffraction analysis using a fixed-bed microreactor. The three different supports gave three different catalytic performances for the catalyst. Best activity was experienced with the modified alumina-supported nickel catalyst. An excess loading amount of nickel hindered the reaction. With different supports, the dispersions of active component were different, the interactions between active component and supports and the reduction ability of the catalyst were all quite different.

99101969 integrated gasification combined cycle power generation Rao, V. N. G. and Raveendran, K. Chem. Ind. Dig., 1998, 11, (2), 82-86, 88. This paper presents a review of integrated gasification combined cycle (IGCC) power generation process and potential applications of this technology. It should be noted that IGCC technology is best suited for a country like India, with solid fuels such as high ash coals, lignites and biomass and a scarcity of petroleum based fuels.

99101970 Manufacture of methanol from synthesis gas passed through hydrogen separation membrane Kobayashi, K. ef al. Jpn. Kokai Tokkyo Koho JP 10 259,148 [98 259,148] (Cl. CO7C31/04), 29 Sep 1998, Appi. 97/66,203, 19 Mar 1997, 6 pp. (In Japanese) MeOH is manufactured via a synthesis gas production step by catalytic reaction of natural gas and steam, a MeOH synthesis step, a MeOH separation step and a MeOH purification step as well as a part of H in the synthesis gas is removed by a hydrogen separation membrane in order to adjust the CO/H ratio at a value appropriate for MeOH synthesis. Hydrogen which is separated by the separation membrane may be used as a fuel for heating in the synthesis gas production step.

99101971 Mathematical model research of coke carrying heat gasifier Zhao, L. and Xu, X. Meitan Zhuanhua, 1998, 21, (3), 63-67. (In Chinese) As the most important component of the coke-heat-carrying coal-fired combined cycle, it is necessary to study the performance and operation of the coke-heat-carrying gasifier. In order to simulate the gasification process and predict the gasifier products according to the characteristics of the gasifier, a mathematical model was established. A comparison between the measurements and simulation results showed the model to be suitable and reliable.

99101972 Methane-rich gas manufacturing apparatus Ema, K. ef al. Jpn. Kokai Tokkyo Koho JP 10 219,264 [98 219,264] (Cl. ClOL3/06), 18 Aug 1998, Appl. 97/41,585, 10 Feb 1997, 4 pp. (In Japanese) The apparatus for the manufacture of methane-rich gas comprises a reactor downstream of low-pressure cyclic-type city-gas manufacturing apparatus for converting reformed gas to methane-rich gas and a CO2 removal apparatus.

99101973 Method for gasification and melting waste solid refuse-derived fuel and recovery of valuable metals lshita, H. et al. Jpn. Kokai Tokkyo Koho JP 10 141,626 [98 141,626] (Cl. F23G5/24), 29 May 1998, Appl. 961301,401, 13 Nov 1996, 12 pp. (In Japanese) The method is carried out by pulverizing the waste, drying the pulverized waste and classifying the dried waste into valuable metals (e.g. copper, aiuminium) for recovery and in-combustible materials (e.g. debris, sand) for removal. Then the separated waste has its volume decreased and is

moulded by adding limestone (and dust from the gasification melting furnace) to obtain refuse-derived fuel. This is followed by charging the obtained fuel into a gasification melting furnace having several zones to generate gases as energy and melting metals and slag for recovery.

99101974 Modeling freeboard gasification in fiuidized bed gasifier (1). Model set-up Tang, Z. ef al. Ranshao Kexue Yu Jishu, 1998,4, (2). 150-156. (In Chinese) The motion of single particle in the freeboard is similar to Brownian movement, which can be described by stochastic theory. Using a Monte- Carlo method (stochastic method), a mathematical model was set-up to simulate the freeboard gasification in a fluidized-bed gasifier. The simulation results fitted well with pilot plant experiment results.

99101975 gasifier. (2).

Modeling of freeboard gasification in fiuidized bed Freeboard gasification

Tang, 2. ef al. Ranshao Kexue Yu Jishu, 1998,4, (2). 157-161. (In Chinese) The- mathematical model of freeboard gasification in a fluidized-bed gasifier was used to investigate the reactivity of the freeboard and the effect of some operation condition changes on reactivity. The reactivity of the freeboard was rather low when there were no fines circulating; with increasing temperature of the outlet gas and enlarging the diameter of the freeboard, this reactivity increased. The effects, however, were not very prominent. Circulation of the fines and secondary air injection were effective methods to increase the freeboard’s reactivity.

99101976 Nila-AlSOB catalyst for the partial oxidation of methane to syngas Jin, R. et al. Wuli Huuxue Xuebao, 1998, 14, (8), 737-741. (In Chinese) For the partial oxidation of methane to syngas, the catalytic performance of Ni/a-AlzOj catalysts with different nickel content was investigated. The reaction took place under the following conditions: in 02 at atmospheric pressure and very high space velocity of 5 x 105 h-‘. Over 8% nickel catalyst at 8Oo”C, optimal CH4 conversion of 91%, CO and Hz selectivity of 94% and 96%, respectively, were obtained. X-ray diffraction analysis indicated that oxidic nickel is the main surface species on the Ni/cw-Alz03 catalyst caicinated at 800°C. Temperature programmed reduction suggested a bimodai nature of oxidic nickel that is ‘fixed’ to the support. The ‘free’ oxidic nickel, which is responsible for the serious carbon deposition on catalyst, appeared as the nickel content was increased up to 12%. Also investigated were the promoter effects of lanthanide oxide (CeO,) and the results showed that CeOZ addition was beneficial to CHI conversion and CO selectivity. An excellent conversion (96.5%) and CO selectivity (96%) were achieved on Ni-Ce(l%Ce)/cu-A1203, at 800°C with a space velocity of 5 x 10’ h-l. Furthermore, under critical reaction conditions, CeOz significantly improved the stability of nickel. After 9 h at 9OO”C, no carbon deposition was found over Ni-Ce(l%Ce)/a-AIZOs. Finally, based on XPS, TPR and XRD results, the promoting mechanism of Ce02 was discussed.

99101977 NiO-alkaline earth oxide catalysts for oxidative methane-to-syngas conversion: influence of alkaline earth oxide on the surface properties and temperature-programmed reduc- tionlreaction by H2 and methane Choudhary, V. R. et al. J. Catal., 1998, 178, (2), 576-585. A study was made of temperature programmed reaction of methane at lOO- 900°C with NiO-MgO, NiO-CaO, NiO-SrO and NiO-mixed alkaline earth oxides with Niialkaline earth element(s) ratio of 1.0 (calcined at 930°C for 4 h). The NiO-CaO, NiO-MgO-CaO and NiO-MgO catalysts showed increasingly superior performance in the oxidative conversion of methane to CO and HZ at a very low contact time (1 ms). However, the presence of a higher alkaline earth oxide (SrO and/or BaO) caused a large decrease or almost complete deactivation of the NiO-containing alkaline. earth oxide(s) catalyst for the reaction. The catalysts before and after reduction were characterized for their relative surface composition of nickel and alkaline earth element(s) by XPS. Because of the reduction, the surface nickel/ alkaline earth(s) ratio for ail the catalysts was decreased; the decrease was, however, very large for the NiO-SrO and all the BaO-containing catalysts.

99101978 Partial oxidation of methane to syngas over PtlA203 and PtlCe0~lAi~03 Yan, Q.-G. ei al. 1303. (In Chinese)

Gaodeng Xuexiao Huaxue Xuebao, 1998, 19, (8), 1300-

Pt/A1203 and Pt/Ce02/A120x catalysts were used during the catalytic oxidation of methane to synthesis gas. A higher activity and selectivity was displayed by catalysts with ceria than those without ceria. A strong interaction existed between ceria and platinum under the reaction conditions, which increase the dispersion of platinum over the catalysts and prevent platinum sintering. The synergistic effect between the platinum and ceria suppressed the activity of Pt/Al203 for combustion reaction and greatly improved the activity and selectivity for partial oxidation. Another role of ceria was to enhance the water gas shift reaction, which leads to increased selectivity for hydrogen.

99101979 Pressure effect on the partial oxidation of methane to syngas Lu, Y. et al. Fenzi Cuihun, 1998, 12, (4), 316-319. (In Chinese) Under conditions of 0.1-0.7 MPa pressure and 973 K, the effect of pressure on the partial oxidation of methane to syngas was tentatively investigated. The gas phase reaction was found to occur markedly at higher pressure,

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