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The Wabash River Integrated Methanol and Power Production from Clean Coal Technologies (IMPPCCT) project is investigating an Early Entrance Coproduction Plant (EECP) concept to evaluate integrated electrical power generation and methanol production from coal and other carbonaceous feedstocks. Research, development and testing (RD&T) that is currently being conducted under the project is evaluating cost effective process systems for removing contaminants, particularly sulfur species, from the generated gas which contains mainly synthesis gas (syngas), CO2 and steam at concentrations acceptable for the methanol synthesis catalyst. The RD&T includes laboratory testing followed by bench-scale and field testing at the SG Solutions Gasification Plant located in West Terre Haute, Indiana. Actual synthesis gas produced by the plant was utilized at system pressure and temperature for bench-scale field testing. 相似文献
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The solubility of sulfur in chromia has been studied in H2-H2O-H2S tagged with35S at 973 and 1173 K at low oxygen and sulfur partial pressures typical for coal gasification-systems. For monocrystalline samples, it has been shown that sulfur-containing species are only present adsorbed on the surface of the specimens and can be removed by ultrasonic cleaning in acetone. The surface coverage after 4 weeks of exposure to H2-H2O-H2S was between 2.8 and 19.3% of a monolayer. In polycrystalline chromia, sulfur was located only in pores and cracks of the sample. In dense, compact areas of the specimens the solubility of sulfur was below the detection limit of autoradiography, which was estimated to be better than 0.17 ppm. 相似文献
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Hydrogen sulfide (H2S) was introduced into a microwave plasma chemical vapor deposition of microcrystalline diamond thin film. Secondary-ion mass spectroscopy showed that sulfur concentration was controlled from 2 × 1015 to 9 × 1017 cm− 3 by controlling the H2S/CH4 ratio, while that of hydrogen concentration was around 5 × 1020 cm− 3 and was independent of the H2S/CH4 ratio. Electrical conductance increased linearly as the S concentration increased from 2 × 1015 to 3 × 1016 cm− 3 without significant deterioration of film crystallinity, i.e., the amount of sp2 phase did not increase. Non-ohmic conduction was converted to ohmic conduction when the S concentration reached 9 × 1017 cm− 3 by increasing the H2S/CH4 ratio to 30,000 ppm. This modification was consistent to the formation of a graphitic phase by heavy S-doping, which was identified by Raman spectra and surface morphology. 相似文献
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Conductive polymer/sulfur composite materials were prepared by heating the mixture of polyacrylonitrile (PAN) and sublimed sulfur. During the heating process, PAN was dehydrogenated by sulfur, forming a conductive main chain similar to polyacetylene. At the same time, the high‐polarity functional group –CN cyclized at the melt state, forming a thermally stable heterocyclic compound in which sulfur was embedded. The nanodispersed composites showed excellent electrochemical properties. Tested as cathode material in a non‐aqueous lithium cell based on poly(vinylidene fluoride) (PVDF) gel electrolyte at room temperature, the composite exhibited a specific capacity up to 850 mA h g–1 in the initial cycle. Its specific capacity remained above 600 mA h g–1 after 50 cycles, about five times that of LiCoO2, and recovered partly after replacement of the anode with a fresh lithium sheet. The utilization of the electrochemically active sulfur was about 90 % assuming a complete reaction to the product, Li2S. 相似文献
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论述了金川有色金属公司现行高冰镍精炼工艺技改的必要性。在综合国内外高冰镍精炼技术的基础上,结合金川有色金属公司的实际,重点阐述了高冰镍硫酸湿法精炼和氯化精炼工艺的优缺点。指出,现行高冰镍精炼工艺的改造应吸取氯化精炼和硫酸湿法精炼两种工艺的长处,稳妥地向高冰镍全湿法精炼过渡。文中还对该公司镍产品结构调整提出看法。 相似文献
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