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101.
Novel and Ideal Zirconium-Based Dense Membrane Reactors for Partial Oxidation of Methane to Syngas 总被引:5,自引:0,他引:5
A novel and ideal dense catalytic membrane reactor for the reaction of partial oxidation of methane to syngas (POM) was constructed from the stable mixed conducting perovskite material of BaCo0.4Fe0.4Zr0.2O3– and the catalyst of LiLaNiO/-Al2O3. The POM reaction was performed successfully. Not only was a short induction period of 2 h obtained, but also a high catalytic performance of 96–98% CH4 conversion, 98–99% CO selectivity and an oxygen permeation flux of 5.4–5.8 mlcm–2min–1 (1.9–2.0 molm–2S–1Pa–1) at 850°C were achieved. Moreover, the reaction has been steadily carried out for more than 2200 h, and no interaction between the membrane material and the catalyst took place. 相似文献
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104.
MnOx promotional effects on olefins synthesis directly from syngas over bimetallic Fe‐MnOx/SiO2 catalysts
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Zhengpai Zhang Weiwei Dai Xin‐Chao Xu Jun Zhang Bianfang Shi Jing Xu Weifeng Tu Yi‐Fan Han 《American Institute of Chemical Engineers》2017,63(10):4451-4464
The direct synthesis of lower olefins via the Fischer‐Tropsch reaction (FTO) has been performed over a series of Fe‐MnOx/SiO2 catalysts. The addition of MnOx could improve the dispersion of iron species, and promote the reduction of iron oxide during the activation and subsequent carburization. Moreover, the results of characterization demonstrated that MnOx could enhance the surface basicity of the catalysts due to electronic effects and promote the formation of iron carbides. For the first time, the intrinsic power‐law kinetics for FTO was obtained for both Fe20/SiO2 and Fe20‐Mn1/SiO2 catalysts. Kinetic parameters and structure characterizations indicated that MnOx could facilitate the CO dissociation on the catalyst surface, thus enhancing the adsorption strength and capacity of surface carbonaceous intermediates. The weak hydrogenation of carbonaceous species would boost the selectivities toward lower olefins. Finally, a plausible mechanism for FTO, involving the promotional effects of MnOx on Fe, has been proposed. © 2017 American Institute of Chemical Engineers AIChE J, 63: 4451–4464, 2017 相似文献
105.
Thermodynamic analysis and optimization of RWGS processes for solar syngas production from CO2
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Marcus Wenzel Liisa Rihko‐Struckmann Kai Sundmacher 《American Institute of Chemical Engineers》2017,63(1):15-22
Process systems were investigated for syngas production from CO2 and renewable energy (solar) by the reverse water‐gas shift (RWGS) and the reverse water‐gas shift chemical looping (RWGS‐CL) process. Thermodynamic analysis and optimization was performed to maximize the solar‐to‐syngas (StS) efficiency ηStS. Special emphasis was laid on product gas separation. For RWGS‐CL, maximum StS efficiencies of 14.2 and 14.4% were achieved without and with heat integration, respectively. The StS efficiency is dictated by the low overall efficiency of H2 production. RWGS‐CL is most beneficial for the production of pure CO, where the StS efficiency is one percent point higher compared to that of the RWGS process with heat integration. Heat integration leads to significant reductions in external heat demand since most of the gas phase process heat can be integrated. The StS efficiencies for RWGS and RWGS‐CL achieve the same level as the reported values for solar thermochemical syngas production. © 2016 American Institute of Chemical Engineers AIChE J, 63: 15–22, 2017 相似文献
106.
介绍壳牌煤气化工艺流程中的合成气反吹系统的反吹介质可由洗涤后的粗合成气改为高温高压氮气。改造后 ,出气化装置的合成气组分既可满足下游装置的工艺要求 ,又可节省大量的工程投资 相似文献
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108.
煤制合成气脱砷技术及净化剂的研究开发 总被引:1,自引:0,他引:1
本文介绍了煤制合成气脱砷技术及脱砷剂的开发及工业应用结果。试验表明, TAS-02 型脱砷剂适用于高水汽比、高CO水煤气气氛的脱砷净化, 稳定性良好, 有较高的砷容和脱砷净化效果。 相似文献
109.
《International Journal of Hydrogen Energy》2020,45(20):11593-11604
Biogas is a renewable biofuel that contains a lot of CH4 and CO2. Biogas can be used to produce heat and electric power while reducing CH4, one of greenhouse gas emissions. As a result, it has been getting increasing academic attention. There are some application ways of biogas; biogas can produce hydrogen to feed a fuel cell by reforming process. Urea is also a hydrogen carrier and could produce hydrogen by steam reforming. This study then employes steam reforming of biogas and compares hydrogen-rich syngas production and carbon dioxide with various methane concentrations using steam and aqueous urea solution (AUS) by Thermodynamic analysis. The results show that the utilization of AUS as a replacement for steam enriches the production of H2 and CO and has a slight CO2 rise compared with pure biogas steam reforming at a temperature higher than 800 °C. However, CO2 formation is less than the initial CO2 in biogas. At the reaction temperature of 700 °C, carbon formation does not occur in the reforming process for steam/biogas ratios higher than 2. These conditions led to the highest H2, CO production, and reforming efficiency (about 125%). The results can be used as operation data for systems that combine biogas reforming and applied to solid oxide fuel cell (SOFC), which usually operates between 700 °C to 900 °C to generate electric power in the future. 相似文献
110.
采用吸附相反应技术(APRT)制备了Cu基催化剂,并用XRD、HRTEM、H2-TPR等表征手段进行了分析。结果表明催化剂中的Cu良好分散于载体表面,粒径在5~10 nm。在液相乙醇体系合成气制甲醇的反应中,该Cu基催化剂对第一步形成中间产物甲酸乙酯的催化活性远高于工业催化剂。APRT制备的催化剂与其他催化剂(包括工业催化剂)在液相合成气制甲醇的两步反应中表现出的显著差异,不仅说明APRT催化剂具有不同的结构特点,也表明甲酸乙酯的形成和进一步的加氢的活性位是不同的。 相似文献