共查询到19条相似文献,搜索用时 93 毫秒
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松香歧化非贵金属催化剂的研究 总被引:1,自引:0,他引:1
本文采用先进的纳米技术制备催化剂,开发出了用于松香歧化反应的非贵金属纳米催化剂。对歧化松香的制备工艺进行了考察,实验表明溶胶-凝胶-沉淀法制备的mN/IL-Ti催化剂,在500℃焙烧2.5h,经预处理(用氢气在300℃还原3h),具有较高的催化活性。并得出歧化松香的最佳制备工艺为:反应温度270℃,反应时间3h,催化剂用量为2.5%。 相似文献
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用非贵金属催化剂制备歧化松香的研究 总被引:5,自引:0,他引:5
在自己组装的常压鼓泡气体循环反应装置上,考察了非贵金属催化剂及反应条件对松香歧化反应的影响,制备出活性好,无脱羧现象的“蛋壳型”非贵金属催化剂,在220℃反应温度下,制备出符合工业要求的特级歧化松香(枞酸〈0.5%,去氢枞酸〉50%)取得了松香歧化用非贵金属催化剂小试制备的较佳结果。 相似文献
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ZnO催化合成歧化松香甘油酯反应的研究 总被引:1,自引:0,他引:1
以歧化松香和甘油为原料,ZnO为催化剂,进行歧化松香甘油酯合成反应的研究。考察了原料配比、催化剂用量、反应温度、反应时间、搅拌速度及保护气种类对酯化反应进度的影响,确定了催化酯化合成歧化松香甘油酯的最佳工艺条件为:原料歧化松香与甘油的摩尔比2.0∶1.0、催化剂用量0.2%(以歧化松香计)、反应温度270℃、反应时间3.0 h、搅拌速度400 r/min、CO2作保护气。在线采样跟踪研究酯化反应的动力学实验数据,运用Eviews软件回归分析,确定不同温度下反应体系的动力学参数,其中反应级数为一级,阿累尼乌斯方程中指前因子为k0=1.372×104min-1和反应活化能为Ea=66.019 kJ.mol-1。 相似文献
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以松香为原料、改性Pd/C为催化剂、200#油为溶剂及N2为保护气,进行松香催化歧化反应集总动力学的研究。在消除内外扩散影响的条件下,在线跟踪48315~53315 K的反应产物并用毛细管柱气相色谱法测定反应体系组成随时间的变化关系。根据松香歧化反应机理和特点,借鉴集总思想和方法,按结构族组成和动力学相近原则划分该复杂反应体系的集总组分,构建了Pd/C上松香歧化集总反应网络,建立了枞酸型树脂酸、海松酸型树脂酸、氢化枞酸型树脂酸、氢化海松酸型树脂酸和脱氢枞酸五集总动力学模型;采用Levenberg-Marquart法,以Matlab编程和SPSS数理统计软件估算了模型参数,得到枞酸型树脂酸脱氢、加氢,海松酸型树脂酸加氢反应过程的活化能分别为11139 kJ·mol-1、10876 kJ·mol-1、9735 kJ·mol-1,结果表明,所建动力学模型与实验数据吻合良好,并能预测反应在54315 K的集总组分浓度分布。 相似文献
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On the surface of a Fe catalyst carbon monoxide disproportionates into C (carbon black) and CO2. Kinetic parameters of this reaction (reaction rate constant, order, and occupancy of catalyst surface) were established in the range of temperatures 430–490°C. At the beginning of the process in all cases an induction period was observed. Under definite conditions the process develops with oscillating dynamics. Induction period and oscillations indicate an autocatalytical nature of the process. The distribution of the Fe catalyst in the profile of the reaction zone (in the bulk of carbon black and on the surface of small crystals) was investigated. 相似文献
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N-甲基吗啉对甲苯歧化与烷基转移催化剂的影响 总被引:1,自引:0,他引:1
N-甲基吗啉是芳烃联合装置中的抽提溶剂,含有少量进入抽提产品之一的甲苯。研究了C9芳烃原料中N-甲基吗啉对ZA-92甲苯歧化与烷基转移工业催化剂催化性能的影响。实验结果表明,在3.0 MPa、空速1.5 h-1、n(氢)∶n(烃)=6.7∶1、385 ℃条件下,原料中N-甲基吗啉质量分数≤100×10-6时,反应24 h后,催化剂仍具有良好的活性;N-甲基吗啉质量分数为50×10-6时,反应500 h后催化剂活性明显下降。 相似文献
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S. Surez M. Yates A.L. Petre J.A. Martín P. Avila J. Blanco 《Applied catalysis. B, Environmental》2006,64(3-4):302-311
Monolithic catalysts based on Rh/TiO2–sepiolite were developed and tested in the decomposition of N2O traces. Several effects such as the presence of NO, O2 and NO + O2 in the gas mixture, the catalysts pre-treatment and the metal loading were evaluated. The system was extremely sensitive to the amount of rhodium, passing through a maximum in the catalytic activity at a Rh content of 0.2 wt.%. It has been demonstrated that both NO and O2 compete for the same adsorption sites as N2O; however, this effect was not as severe as for other previously reported Rh systems. For NO + O2 gas mixtures the inhibition effect was stronger than when only NO or O2 was present. Analysis of the pre-reduced sample by XPS showed Rh mainly in the metal state, even after treatment with N2O + O2 mixtures, suggesting that the oxygen consumption observed in the Temperature Programmed Reaction experiments was related to the oxygen uptake by vacancies in the support. The presence of sepiolite in the support preparation and its role as a matrix over which TiO2 particles were distributed, seems to play an important effect in the migration process of oxygen species through the support vacancies. The Rh/TiO2 monolithic system is an attractive alternative for the elimination of N2O traces from stationary sources due to the combination of high catalytic activity with a low pressure drop and optimum textural/mechanical properties. 相似文献
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