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固体超强酸SO_4~(2-)/ZrO_2催化合成马来酸单糠醇酯的研究 总被引:5,自引:1,他引:4
合成了SO42-/TiO2、SO42-/Fe2O3、SO42-/SnO2、SO42-/ZrO2等4种固体超强酸,用作由糠醇和马来酐合成马来酸单糠醇酯的催化剂。结果表明,SO42-/ZrO2的催化活性最好,其较佳活化温度为590℃。用正交实验L9(33)筛选的较佳酯化条件为:马来酐/糠醇(摩尔比)=1:1.1,反应温度45℃,反应时间2.5 h,催化剂用量为总反应物质量的10%,平均收率92.6%。 相似文献
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对优化后的纳米氢氧化铜催化剂在糠醛加氢制糠醇的反应中进行了工艺条件考察,并对产物用气相色谱进行转化率和选择性的测定,最终优化了反应工艺条件。即在反应温度为200 ℃、反应压力为6 MPa、催化剂负荷量为200 g(糠醛/g催化剂.h)、反应时间为3 h的条件下,通过谱图分析与计算得到糠醛转化率为97%,糠醇选择性达96.6%。 相似文献
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以铜铝合金和钴铝合金为原料制备了Raney铜和Raney钴催化剂,利用XRF,XRD,BET等方法分析了催化剂的组成、晶相结构及表面性质。表征结果显示,Raney铜催化剂表面同时含有Cu0和Cu2O活性物种。考察了催化剂的糠醛加氢性能,并与工业用铜铬催化剂进行了对比。实验结果表明,Raney铜催化剂比铜铬催化剂具有更高的催化反应速率,比Raney钴催化剂具有更好的糠醇选择性,且具有较好的糠醛加氢重复使用性能。当Raney铜催化剂用量为2 g(基于100 mL糠醛),在7.0 MPa、160℃下反应2 h时,糠醛转化率为99.98%,糠醇选择性为96.75%。 相似文献
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以海泡石为载体,用水溶液浸渍法制备了无铬铜基负载型催化剂.用脉冲微反考察了Cu含量、反应温度、反应物注射量等对糠醛常压气相加氢制糠醇催化反应的影响,并用TPR表征催化剂的还原性能.实验结果表明,Cu/Sep催化剂常压下对糠醛气相加氢制糠醇反应具有较好的催化性能.在Cu含量为18.1%的催化剂上、反应温度135℃、常压氢气的条件下,糠醛的转化率及对糠醇的选择性均为100%.TPR表征结果表明,随着催化剂中Cu负载量的增加,Cu分散度逐渐降低,且催化剂中Cu含量与峰顶温度有较好的线性关系. 相似文献
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无溶剂有机合成的促进方法及其前景 总被引:1,自引:0,他引:1
研磨、相转移催化、微波辐射和主-客体包结是用来改善无溶剂有机合成效率的主要方法。采用无溶剂有机合成不仅能减少溶剂的危害,而且能提高反应效率,因此可能成为一种有效的绿色合成方法。由于无溶剂反应体系散热困难和反应速度快,所以它不适合于剧烈放热的反应。为了实现无溶剂有机合成的工业化,应开展相关工程技术和工业设备的研究。 相似文献
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Sunggyu Lee Vetkav R. Parameswaran Irving Wender Conrad J. Kulik 《Petroleum Science and Technology》1989,7(8):1021-1057
The roles played by carbon dioxide in the chemistry of methanol synthesis over CuO/ZnO/A12O3 catalysts have been experimentally investigated. It was concluded based on reaction rate measurements and thermodynamic considerations, that the two reactions that best describe the chemical system of methanol synthesis are the CO2-hydrogenation and water-gas shift reactions. It was also found experimentally that the presence of CO2 is vital for maintaining the catalytic activity. The significance of the study is enhanced by the fact that this was the first such investigation of the global chemistry of methanol synthesis to be based on the novel liquid phase process. It was also observed that the rates of methanol synthesis attained a maximum when the concentration of carbon dioxide in the reactor feed was controlled at a certain optimal value. The optimal CO2 content was found to be a function of the operating temperature and syngas composition. The experimental data are especially important because the apparatus and the operating conditions have been well-defined and carefully chosen to closely simulate industrial reactors. 相似文献
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简述了环氧丙烷的清洁生产技术研究现状,介绍了具有工业应用前景的三种清洁生产技术及存在的问题。着重介绍了国外丙烯环氧化的胶团催化技术,包括胶团催化机理、反应体系设计以及工艺开发。指出选择适用的表面活性剂、催化剂、助催化剂以及工艺开发是胶团催化技术的关键。对采用胶团催化合成环氧丙烷的工业化前景作了展望,建议加强用胶团催化技术生产环氧丙烷的研究和开发。 相似文献
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Wei Gao Mohammad Reza Farahani Muhammad K. Jamil Muhammad K. Siddiqui Hafiz Muhammad Afzal Siddiqui Muhammad Imran 《Petroleum Science and Technology》2017,35(2):183-189
Different approaches have been used to convert the waste materials into a clean syngas or other chemicals such as methanol. Among them, pyrolysis is a good candidate to produce the synthesis gas and volatile matters for industrial and refinery applications. In this work, we studied the kinetic and chemical behavior of three Iranian waste oils through a kinetic model and an experimental study. The experiments carried out in a micro-FB reactor, which is a good option for low emissions. Results showed that the reaction temperature and reaction rate are two of the most important factors for maximum conversion level of fuel. Results also showed an optimum value for reaction rate. The modeling results validated against the experimental measurements and found to be in good agreements. 相似文献
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Sunggyu Lee Vetkav R. Parameswaran Irving Wender Conrad J. Kulik 《Petroleum Science and Technology》2013,31(8):1021-1057
ABSTRACT The roles played by carbon dioxide in the chemistry of methanol synthesis over CuO/ZnO/A12O3 catalysts have been experimentally investigated. It was concluded based on reaction rate measurements and thermodynamic considerations, that the two reactions that best describe the chemical system of methanol synthesis are the CO2-hydrogenation and water-gas shift reactions. It was also found experimentally that the presence of CO2 is vital for maintaining the catalytic activity. The significance of the study is enhanced by the fact that this was the first such investigation of the global chemistry of methanol synthesis to be based on the novel liquid phase process. It was also observed that the rates of methanol synthesis attained a maximum when the concentration of carbon dioxide in the reactor feed was controlled at a certain optimal value. The optimal CO2 content was found to be a function of the operating temperature and syngas composition. The experimental data are especially important because the apparatus and the operating conditions have been well-defined and carefully chosen to closely simulate industrial reactors. 相似文献
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考察了碱度、晶化时间、陈化时间对无模板剂合成小晶粒NaY分子筛的影响关系,确定了最佳合成条件为n(Na2O)/n(SiO2)=0.92、n(H2O)/n(Na2O)=21.7、陈化时间24 h、于100℃下晶化时间12 h。对所合成小晶粒Y分子筛进行组合改性,改性分子筛具有高结晶度、高硅/铝比、酸性适中和二次孔发达等特点。将改性小晶粒Y分子筛应用于加氢裂化催化剂中,并对所制备的催化剂进行活性评价。结果表明,所制备催化剂的反应温度比工业参比剂低5℃;喷气燃料收率稍高于工业参比剂;柴油的十六烷值指数和低温性能均好于工业参比剂;尾油的BMCI值比工业参比剂降低约一半。 相似文献
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综述了ZSM-48分子筛的合成制备及应用研究进展。所选用的模板剂类型、碱金属离子类型与浓度、晶化温度、OH-/SiO2摩尔比等因素均影响ZSM-48分子筛的硅铝比、晶体结构与形貌;进而影响其催化反应性能和应用方向,还主要决定其制备成本。指出:鉴于ZSM-48分子筛独特、适宜的孔道结构及B酸酸位特性,使其在加氢异构反应中具有良好的异构选择性,如何低成本合成制备出低硅铝比、小轴径比的ZSM-48分子筛,成为当前及今后其被工业化应用的关键与研究重点。预期将在生产高品质的润滑油、生物质航煤以及在二甲苯异构化、甲苯歧化等化工原料方面具有广阔应用前景。 相似文献
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过氧化氢(H2O2)的活性氧含量高且降解时副产物只有水,可作为工业常用氧化剂的替代物。H2和O2直接合成H2O2是一种高原子利用效率的绿色合成新技术,有望替代当前传统的工业生产方式,实现H2O2清洁生产与原位选择性氧化的一步集成。综述了H2和O2直接合成H2O2与丙烯环氧化、Fenton废水处理、甲烷氧化等反应的集成,介绍现已取得的成果及面临的挑战,拓宽H2、O2和有机物的原位氧化反应体系,为未来化学品的绿色合成提供新思路。 相似文献