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以合成气合成甲醇催化剂及其进展 总被引:8,自引:0,他引:8
本文概念了甲醇合成催化剂以及新型催化剂的研究开发状况,介绍了各类甲醇合成催化剂,锌铬催化剂,铜基催化剂,耐硫催化以及目前国际上研究最热的液相甲醇合成催化剂,并论述了常用催化剂优缺点。 相似文献
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《化学工业与工程技术》2017,(2):41-45
传统的酯化反应催化剂如浓硫酸、磷酸、对甲苯磺酸虽然具有较高的催化活性,价廉易得,但存在副反应多、对设备腐蚀严重、能耗大、反应废液处理复杂等缺点。因此,寻找可代替传统催化剂的新型酯化催化剂势在必行。介绍了近年来酯化反应中催化剂研究的进展情况,对相转移催化剂、室温离子液体催化剂、无机盐催化剂、树脂类催化剂、分子筛催化剂、杂多酸催化剂、固体超强酸催化剂等不同催化剂的特点进行了总结,比较了各类催化剂使用过程中的优缺点。提出了酯化反应催化剂未来的研究方向,主要在于开发高效环保型绿色催化剂。 相似文献
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文章概述了烯烃骨架异构化催化剂,包括卤化物催化剂、氧化物催化剂和分子筛催化剂。与卤化物催化剂和氧化物催化剂相比,分子筛催化剂表现出了优异的直链烯烃骨架异构化性能。 相似文献
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介绍了XNC-98型甲醇合成催化剂的物理特性和组成,针对鲁奇合成塔的特点,制定了装填方案和操作步骤,详细阐述了该催化剂的升温还原方案和升温还原操作过程,对生产使用情况进行了总结。 相似文献
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介绍了一轴三径氨合成塔内件的结构和流程,叙述了A202、A110—1型催化剂在该塔的装填情况、升温还原方案和升温还原历程。对升温还原的经验和教训进行了总结。生产实践表明,氨合成塔进、出口氨的体积分数分别为2.87%和13.7%,合成氨日产量达到362t。 相似文献
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Continuous transesterification of biodiesel in a helicoidal reactor using recycled oil 总被引:1,自引:0,他引:1
The main problem with biodiesel is the high cost of oils made from oleaginous crops. For this reason, various raw materials have been analysed with a view to reducing production costs and obtaining a product that can compete with the price of petrodiesel. Recycled oil is one of the most promising alternatives in the production of biodiesel because not only is the cheapest raw material but it also avoids the expense of treating the oil as a residue.Another way to reduce costs is to make the process more economical. Conventional technology uses sodium hydroxide as the basic catalyst and large-scale batch reactors, whose mechanical agitation requires high energy consumption due to residence times of at least 60 min and temperatures of 60 °C.In this paper we use a recycled pretreated oil to compare conventional transesterification with continuous transesterification in a tubular reactor. In this reactor the reactants (oil, methanol and sodium hydroxide) flow through a helicoidal tube submerged in a heating bath at 60 °C. The reactor has five outlets distributed non-uniformly to enable samples to be taken at different reaction times. This is to reduce the reaction time and avoid the need for mechanical agitation. With the aim of improving the quality of the biodiesel obtained, we varied the helicoidal system by incorporating a static micromixer and supplying energy in the form of ultrasound from the heating bath. This reactor produced biodiesel and glycerine at compositions roughly equal to those obtained in the batch process (89% FAME content at 75 min) but did so continuously (2.5 mL/min) and just 13 min after the reactants were integrated in a single line using a T device. Both the oil and the biodiesel were characterized and analysed in accordance with European standard UNE EN14214 for biodiesel. 相似文献
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论述了以控制催化剂床层温度的变化来决定还原进程,同时兼顾水汽浓度、出水量及精炼气中氢含量的还原方法。介绍了升温还原过程和操作注意事项,对催化剂应用效果和经济效益进行了总结。结果表明,还原方法改进后,每炉催化剂还原时间比原来缩短18h。 相似文献
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Joo-Hyoung Park Sang Jun Park Hee Ah Ahn In-Sik Nam Gwon Koo Yeo Jeong Ki Kil Young Kee Youn 《Microporous and mesoporous materials》2009,117(1-2):178-184
Libraries consisting of more than 100 zeolite samples were prepared and examined for developing a promising HC trap catalyst. Parallel adsorptions of toluene onto the catalyst samples were conducted over a 10 × 10 array reactor under dry and wet conditions with or without a heating process three knowledge-based conditions for developing an automotive catalyst during the cold-start period. FAU and BEA type zeolites revealed a high performance of toluene adsorption under the dry condition. However, FAU type zeolite significantly decreased the amount of toluene adsorbed in the presence of water in the feed gas stream, mainly due to the hydrophobicity of the catalyst surface. Over Beta type zeolites, the toluene adsorbed was found to be considerably preserved, even after forced desorption temperature-ramping to the warm-up condition of an automotive engine. Li, K, or Ag ion-exchanged Beta zeolites seem to be particularly promising as an HC trap catalyst. 相似文献
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Amomax-10/10H型氨合成催化剂在伍德合成塔的运行总结 总被引:1,自引:0,他引:1
河南中原大化公司30万/t合成氨装置伍德三床层径向氨合成塔运行20年来首次更换催化剂。介绍了Amomax-10/10H型氨合成催化剂的性能;简述了旧催化剂卸出、新催化剂装填及升温还原的过程;总结了Amomax-10/10H型催化剂的使用效果和有待完善的问题。结果表明,采用Amomax-10/10H型催化剂可缩短还原时间,可不启用开工加热炉,降低了合成气压缩机和冰机功耗。 相似文献
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This research aims at increasing the utilization of platinum-ruthenium alloy (Pt-Ru) catalysts and thus lowering the catalyst
loading in anodes for methanol electrooxidation. The direct methanol fuel cell’s (DMFC) anodic catalysts, Pt-Ru/C, were prepared
by chemical reduction with a reducing agent added in two kinds of solutions under different circumstances. The reducing agent
was added in hot solution with the protection of inert gases or just air, and in cold solution with inert gases. The catalysts
were treated at different temperatures. Their performance was tested by cyclic voltammetry and potentiostatic polarization
by utilizing their inherent powder microelectrode in 0.5 mol/L CH3OH and 0.5 mol/LH2SO4 solution. The structures and micro-surface images of the catalysts were determined and observed by X-ray diffraction and
transmission electron microscopy, respectively. The catalyst prepared in inert gases showed a better catalytic performance
for methanol electrooxidation than that prepared in air. It resulted in a more homogeneous distribution of the Pt-Ru alloy
in carbon. Its size is small, only about 4.5 nm. The catalytic performance is affected by the order of the reducing agent
added. The performance of the catalyst prepared by adding the reductant at constant temperature of the solution is better
than that prepared by adding it in the solution at 0°C and then heating it up to the reducing temperature. The structure of
the catalyst was modified, and there was an increase in the conversion of ruthenium into the alloyed state and an increase
in particle size with the ascension of heat treatment temperature. In addition, the stability of the catalyst was improved
after heat treatment.
Translated from Journal of Harbin Institute of Technology, 2006, 38 (4): 541-545 [译自: 哈尔滨工业大学学报] 相似文献
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Changsui Zhao Liangsheng Lin Keliang Pang Wenguo Xiang Xiaoping Chen 《Fuel Processing Technology》2010,91(8):805-809
The gasification characteristics of natural coke from Peicheng mine with steam were investigated in a fluidized bed reactor. The effects of catalyst type, composition and dosage of catalyst on the yield, components and heating value of product gas, and carbon conversion rate were examined. The results show that fluidized bed gasification technology is an effective way to gasify natural coke. Also the results indicate that individual addition of K-, Ca-, Fe-, Ni-based catalyst effectively increases the gasification reaction rate of the natural coke samples. With the increase in catalyst dosage, the yield and heating value of product gas per hour increase obviously, and carbon conversion rate is improved substantially. Each of aforementioned catalysts has similar catalytic effect and trend, among which the effect of Ca-based catalyst is a little weaker. The optimum metal atom ratio of mixed catalyst is Fe/Ni/others = 35/55/10, and the mixed catalyst displays maximum catalytic performance when the catalyst dosage in the natural coke is about 4%. The experimental findings provide an interesting reference for large-scale development and utilization of natural coke. 相似文献
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介绍了氨合成工艺流程和设备配置,论述了DNCA型氨合成催化剂的物理特性和应用情况,详细阐述了DNCA催化剂的装填要领、升温还原方案及注意事项,结合生产运行工艺指标和操作控制要点,对DNCA催化剂使用效果进行了总结。 相似文献