共查询到17条相似文献,搜索用时 156 毫秒
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随着各国新能源行业的兴起,氢能成为最具发展潜力的可再生能源。利用生物油进行催化重整是一种优良、高效的制氢方法,同时拓宽了生物油高值化利用的途径。本文对近年来该领域内的相关研究进行综述,重点介绍了原料对重整反应的影响(不同来源生物油及其模化物)、催化剂特性对重整反应的影响(负载贵金属与非贵金属)以及操作条件对重整反应的影响,对新兴的微波催化重整技术进行了简要介绍,并针对目前该领域所面临的困难提出了一些展望及发展方向,为生物油催化重整制氢提供重要理论依据。 相似文献
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生物质热利用过程中产生的焦油极易造成管路腐蚀堵塞,是当前亟待解决的关键问题。焦油的催化重整制氢是一种有效的生物质高值化利用技术。以常压气化炉运行过程中产生的焦油为研究对象,利用杏壳制备催化剂炭载体,并负载催化金属以制备重整焦油用碳基催化剂;使用制备的碳基催化剂开展焦油水蒸气催化重整实验,并对比了不同负载金属的催化效果。结果表明:当采用单金属催化剂对焦油进行催化重整时,最佳工况为800℃、通入水蒸气与焦油质量比为3、焦油与催化剂质量比为2时,氢气产量高达91.52 g H2 (每1 kg焦油),焦油转化率为93.30%。Ni-Co/C复合催化剂表现出比单金属催化剂更强的活性。 相似文献
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氢能是公认的较为理想的绿色能源,开发利用氢能不仅能摆脱对传统化石能源的长期依赖,还能解决能源短缺及环境污染问题,低成本且高效环保地制取氢气有利于中国能源结构转变与可持续发展战略的实施,其中利用可再生生物质衍生物重整制氢技术越来越受到人们的关注。从化学与能源角度出发,综述和评论了国内外以生物醇类、苯酚类、酸类三大主要生物质衍生物为原料重整制氢的研究,分析了这些生物质衍生物重整制氢的反应机理,集中阐述了催化剂和载体对重整制氢的作用效果,以及催化体系所面临的问题及改进办法。结合目前制氢发展着重于催化剂改性、载体优化、工艺改进等方面的研究趋势,提出未来可深入开发新型载体和助剂、丰富催化剂体系、整合各种制氢工艺的研究方向。 相似文献
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A catalyst consisting of Ru (5%) dispersed on 15% MgO/Al2O3 carrier exhibits high activity and selectivity, as well as satisfactory stability with time on stream, under conditions of steam reforming of acetic acid, a model compound for pyrolysis oil. The presence of MgO in the catalyst formulation is shown to be related to oxygen and/or hydroxyl radical spillover from the carrier to the metal particles. A series of Ru/MgO/Al2O3 catalysts supported on cordierite monoliths, ceramic foams and γ-Al2O3 pellets were prepared and tested for the production of hydrogen by catalytic steam reforming of the aqueous fraction of bio-oil. All different structural forms of the catalyst exhibited satisfactory activity, converting completely the bio-oil, good selectivity toward hydrogen and satisfactory stability with time on stream. However, the catalyst supported on pellets exhibited the best catalytic performance, among all catalysts investigated. Reforming reactions, and thus hydrogen production, are favoured at high temperatures and low space velocities. Coking is one of the most significant problems encountered in these processes. It was found that only a small part of the incoming carbon is deposited on the catalyst surface, which is mainly present as CHx. However, coke deposition is more intense on the reactor wall above the catalytic bed, due to homogeneous polymerization of unstable ingredients of bio-oil. 相似文献
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为了“碳达峰,碳中和”的目标,开发以可再生能源为主体的绿色制氢技术势在必行。基于原位汽化策略,本文在自主研发的固定床/流化床催化重整一体式反应装置上开展水相生物油催化重整制氢对比实验。结果发现,在经原位汽化改进后的催化重整制氢工艺中,流化床内水相生物油转化效率(95%左右)明显高于固定床(80%左右),两种反应体系中的H2选择性均能100%保持较长时间稳定,但在反应进行到100min左右时,固定床反应体系中出现了明显的催化剂积炭失活现象,而流化床体系中催化剂始终保持较高活性,未发现积炭生成。从反应后液相产物分析可以发现,流化床反应体系中水相生物油各组分接近完全转化,而固定床反应体系中除有少量乙酸和苯酚残留外,还有少量酮类物质产生(丙酮等)。因此,原位汽化策略可以有效促进水相生物油催化重整制氢过程,结合流化床中催化剂的流化效果,将极大促进生物质-生物油-氢气的产业链推广进程。 相似文献
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Zhongkai Zhao Yohanes A. Situmorang Ping An Nichaboon Chaihad Jing Wang Xiaogang Hao Guangwen Xu Abuliti Abudula Guoqing Guan 《化学工程与技术》2020,43(4):625-640
In the future, hydrogen will be an important energy carrier and industrial raw material. Catalytic steam reforming of bio-oils is a promising and economically viable technology for hydrogen production. However, during the reforming process, the catalysts are rapidly deactivated due to coke formation and sintering. Thus, maintaining the activity and stability of catalysts is the key issue in this process. Optimized operation conditions could extend the catalyst lifetime by affecting the coke morphology or promoting coke gasification. This article summarizes the recent developments in the field of catalytic steam reforming of bio-oils, focusing on the operation conditions, the properties of the catalysts, and the effects of the catalyst supports. The expected insights into the catalytic steam reforming of bio-oils will provide further guidance for hydrogen production from bio-oils. 相似文献
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氢能是一种清洁的二次能源,具有绿色环保、零污染、零碳排放等优点。芳烃蒸汽重整制氢原料来源广、单位体积原料产氢量高,在重油焦油清除升级、便携式移动制氢等领域极具应用价值,其核心在于高性能催化剂的开发。文章首先从芳烃重整反应特性、反应网络、动力学模型构建和吸附解离等方面对其反应动力学及机理进行了概述,认为采用热力学理论计算、先进的原位表征技术和严密的逻辑论证实验等综合手段是加深反应动力学和机理认知的关键;其次,按照催化剂组成分类,评述了不同活性组分、载体及助剂的特点,基于镍基双金属活性组分的协同效应、钙钛矿载体的强储/释氧能力和碱性助剂的酸调控作用,指出碱性助剂改性的负载型镍基双金属钙钛矿催化剂是其发展方向。 相似文献
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Hydrogen was prepared via catalytic steam reforming of bio-oil which was obtained from fast pyrolysis of biomass in a fluidized bed reactor. Influential factors including temperature, weight hourly space velocity (WHSV) of bio-oil, mass ratio of steam to bio-oil (S/B) as well as catalyst type on hydrogen selectivity and other desirable gas products were investigated. Based on hydrogen in stoichiometric potential and carbon balance in gaseous phase and feed, hydrogen yield and carbon selectivity were examined. The experimental results show that higher temperature favors the hydrogen selectivity by H2 mole fraction in gaseous products stream and it plays an important role in hydrogen yield and carbon selectivity. Higher hydrogen selectivity and yield, and carbon selectivity were obtained at lower bio-oil WHSV. In catalytic steam reforming system a maximum steam concentration value exists, at which hydrogen selectivity and yield, and carbon selectivity keep constant. Through experiments, preferential operation conditions were obtained as follows: temperature 800~850℃, bio-oil WHSV below 3.0 h-1, and mass ratio of steam to bio-oil 10~12. The performance tests indicate that Ni-based catalysts are optional, especially Ni/a-Al2O3 effective in the steam reforming process. 相似文献
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生物油重整制合成气不仅能充分利用生物油中的成分,同时也展现了生物油转化为化学品的高值利用潜能。将载氧体NiFe2O4和Ni基催化剂耦合得到催化耦合化学链反应体系,为了比较催化剂的影响机制,分别构建了Ni/Si-NiFe和Ni/VR-NiFe催化耦合化学链反应体系,并以愈创木酚、乙酸和乙醇的纯物质及其混合液作为生物质热解液的模拟物,通过水蒸气重整实验考察了催化剂配比、反应温度、水碳比和反应时间对重整产物分布的影响。基于反应条件的筛选进一步通过寿命试验和BET、SEM表征,验证了反应体系的稳定性。最后,通过单组分及混合液体重整反应系统分析了化学链耦合催化反应体系的重整机制,为生物质热转化制备化学品提供了重要的理论支撑。 相似文献
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为了应对潜在的氢能利用需求,乙醇水汽重整反应受到了越来越多的关注。镍基催化剂因其高活性、高选择性以及成本优势而极具应用前景,同时在提高催化剂稳定性、降低反应温度、提高氢气收率等方面仍然有进一步发展的空间。更深入认识反应机理、失活机制和催化剂的构效关系是开发高效催化剂的关键。本文对近年来镍基乙醇重整催化剂的研究进展进行了整理总结,首先介绍了通过原位光谱、动力学以及理论计算等手段取得对反应中间物种与反应机理的新认识,分析了催化剂失活的主要原因,并且讨论了镍基催化剂的活性相、尺寸效应、助剂效应,双金属效应等问题,最后简单介绍了得益于基础研究进展的催化剂合成方面的成果,并提出对镍基乙醇水蒸气重整(ESR)剂未来发展的看法:在线/原位表征技术和理论计算将有助于真正理解镍基ESR催化剂的构效关系和反应机理,而新材料,如碳化钼的应用可能在提高催化剂反应性能方面起到作用。 相似文献