乙烯齐聚的连续化反应研究

在四元催化体系间歇釜式反应的基础上 ,本文对乙烯齐聚的连续化反应进行了系统研究 ,设计并安装了一套连续化反应装置 ,包括预反应器、反应器和闪蒸后处理装置。在连续化反应装置上 ,分别考察了催化剂进料速度、反应压力和催化剂浓度对乙烯齐聚连续化反应的影响 ,同时获得了连续化反应的最佳反应条件。经过研究发现 ,该四元催化体系的间歇釜式反应的最佳反应条件 ,也同时是连续化反应的最佳反应条件 ,齐聚反应的催化活性、C=4 -10 的选择性、1-C=4 -10 的线性选择性及产物分布等基本相同。实验证明 ,该连续化反应工艺流程可行 ,可作为未来工业化的模型装置。     

羟胺-环己酮法肟化反应效率的影响因素及改进措施

介绍了羟胺-环己酮法中环己酮肟化反应的原理及工艺流程,讨论了反应温度、环己酮进料的分布、缓冲溶液的pH值、脉冲速度等因素对肟化反应效率的影响,针对各个影响因素提出了改进肟化反应条件的措施并应用于生产实践,提高了肟化反应效率。     

过渡金属Ni催化的硼化反应研究进展

介绍了近年来过渡金属Ni催化的硼氢化反应、双硼化反应、β-硼化反应、硼化开环反应以及硼化偶联反应的研究进展,并对相关的反应机理进行了讨论。     

磷酸酯淀粉合成反应动力学研究

本文研究了淀粉磷酸酯化的反应动力学过程,讨论了复合磷酸盐配比、复合磷酸盐用量等反应条件对取代度的影响,不同反应温度对淀粉磷酸酯化反应速率的影响。结果表明,提高反应温度,反应速率明显加快,淀粉磷酸酯化反应符合二级动力学的反应机理,磷酸酯化反应的表观活化能Ea=14.6 kJ·mol-1。     

CO、CO_2及其共存体系的甲烷化反应

介绍了甲烷化的反应体系,CO、CO2甲烷化反应的机理;比较了CO体系、CO2体系和CO、CO2共存体系的甲烷化反应特点以及三种反应体系对催化剂的要求;综述了适用于不同体系催化剂的研究进展,并重点介绍了多种催化剂的载体、助剂与活性组分之间的相互作用方式以及几种催化剂对碳氧化物甲烷化反应的催化机理;甲烷化反应的应用方向逐步从合成氨、合成气制天然气向燃料电池、焦炉煤气等方向扩展,对反应体系的研究也由CO甲烷化体系向CO2甲烷化体系和共存体系方向发展;复合载体负载的多金属催化剂成为现在甲烷化催化剂的主要研究方向,纳米颗粒催化剂、等离子体等技术开始应用于甲烷化催化剂。     

乙醇胺还原胺化合成乙二胺的催化剂研究进展

介绍了乙醇胺催化还原胺化反应合成乙二胺的机理及影响反应的工艺条件:叙述了乙醇胺还原胺化反应的催化剂研究进展,讨论了催化活性中心、催化剂栽体、助剂等对胺化反应的影响.认为乙醇胺还原胺化法是一种适合于大规模、连续化生产乙二胺的清洁工艺,将成为未来发展的必然趋势.     

乙醇胺缩合胺化反应合成乙二胺研究进展

乙醇胺（MEA）缩合胺化反应是一种绿色、高效的乙二胺（EDA）催化合成技术。本文综述了MEA缩合胺化反应合成EDA的催化反应过程、缩合胺化催化剂及胺化产物分离纯化技术的最新研究进展和动向，重点探讨了缩合胺化反应机理、反应热力学及动力学、催化剂酸性及孔道结构对反应性能的影响、催化剂失活、胺化产物分离纯化技术等，总结了缩合胺化反应合成EDA工艺过程中存在的技术问题。提出通过制备多级孔道沸石分子筛催化剂实现择形催化与高效扩散之间的协调统一；通过强化分子筛催化剂改性方法研究，实现催化剂表面酸性的精确调控。在择形催化和酸催化的协同作用下，有望从根本上解决缩合胺化反应中存在的技术问题，加快缩合胺化反应工艺技术的工业化应用普及。     

铟、锌参与的水相烯丙基化反应

水相烯丙基化反应是水相金属有机反应中研究比较深入的反应之一,许多金属如铟、锌、锡、锰、镁、锑等均可参与水相烯丙基化反应。本文概述了近年来研究比较多的铟、锌金属参与的水相烯丙基化反应的研究情况。     

己内酰胺肟化塔改造的技术性探讨

从肟化反应原理和反应条件着手,分析了影响肟化反应效率的各种因素,结合现有的工艺、设备情况,经过计算,提出了己内酰胺肟化塔改造的方案并付诸实施,使肟化反应效率得到大幅度的提高.     

反应条件对甲烷化法去除重整氢气中CO的影响

研究了在采用甲烷化法去除重整氢气中CO的过程中,反应温度、CO浓度和CO₂浓度对3个竞争反应即CO甲烷化反应、CO₂甲烷化反应、逆变换反应（RWGS）的影响。实验结果表明,随着温度升高,CO、CO₂甲烷化反应速率均增大,但CO甲烷化的选择性降低。CO浓度对CO甲烷化反应速率的影响在高温时较为明显,反应速率随CO浓度的升高而增大;CO对CO₂甲烷化反应的影响在较低温度下较为显著,CO₂甲烷化反应速率随CO浓度的升高而减小,表明CO对CO₂的甲烷化具有抑制作用,因而随着CO浓度的升高,选择性增大。另一方面,CO₂浓度对CO甲烷化反应几乎没有影响,而CO₂甲烷化反应速率和RWGS反应速率均随CO₂浓度的升高而增大,该趋势在高温下更加显著,并对3个竞争反应的宏观动力学进行了初步研究。     

化学工业中的新酸碱催化过程

介绍了1990年以来全世界化学工业中投入生产的新酸碱催化过程。这些过程采用的催化剂主要为沸石,杂多酸,离子交换树脂,改性氧化锆和超强碱等,涉及的反应类型包括均相和多相催化的液相和气固相反应。同时对酸碱催化未来的研究方向进行了评述。     

Catalysis by molecular design

The possibilities of molecular design in the development of new catalysts and catalytic technologies are discussed with the data obtained recently at the Boreskov Institute of Catalysis as particular examples. Examples from the following areas are presented: homogeneous catalysis with metal complexes, heterogeneous catalysis with anchored metal complexes, heterogeneous catalysis with catalysts prepared via anchored metal complexes and organometallics, catalysis of olefin polymerization, catalysis by metals, catalysis by oxides, catalysis by zeolites, catalysis by heteropolyacids, catalysis with nontraditional oxidants and biomimetic catalysis.     

杂多酸催化剂在碳酸二甲酯制备中的应用研究

研究了在碳酸二甲酯制备中,借助于杂多酸的多相酸催化作用,将杂多酸负载在其它载体上.采用间歇釜式反应器,对反应压力和温度进行讨论,得到了杂多酸催化剂用于催化精馏的最佳温度和压力,确定了催化剂的制备方法和适当载体.     

固载型杂多酸催化剂研究新进展

以活性炭、硅胶、MCM-41分子筛、炭化树脂、膨润土、TiO2和-γA l2O3等为载体,详尽地介绍了固载型杂多酸的类型、制备方法、结构与表征、主要性质及其应用领域,概括了它作为特种催化剂的研究现状,并展望了未来的发展前景。     

A comparison of cesium-containing heteropolyacid and sulfated zirconia catalysts for isomerization of light alkanes

The heteropolyacid H₃PW₁₂O₄₀ and its cesium salts Cs_xH_3-x PW₁₂O₄₀ (x = 1, 2, 2.5, 3) were synthesized, characterized and tested as catalysts for hydrocarbon reactions. All samples were characterized by a variety of techniques including elemental analysis, X-ray diffraction, dinitrogen adsorption, thermal gravimetric analysis and ammonia sorption. Results from these methods confirmed that pure cesium salts were prepared without significant contamination by amorphous oxide phases. Incorporation of cesium into the heteropolyacid decreased the acidic protons available for catalysis, increased the specific surface area, and increased the thermal stability. The heteropolyacids were tested as catalysts for butane skeletal isomerization, pentane skeletal isomerization and 1-butene double bond isomerization. For comparison, the activity of sulfated zirconia, a well-studied strong acid catalyst, was also evaluated for the three probe reactions. On a per gram basis, the Cs₂HPW₁₂O₄₀ sample was the most active heteropolyacid, presumably due to its high surface area. This sample was more active than sulfated zirconia for pentane skeletal isomerization and 1-butene double bond isomerization. However, sulfated zirconia was more effective for butane skeletal isomerization. Since the pentane and 1-butene reactions were monomolecular in nature, whereas butane isomerization was bimolecular, restrictions inside the micropores of the heteropolyacid may inhibit the formation of long chain intermediates. Interestingly, trace butenes were required to initiate butane isomerization reactions on sulfated zirconia, whereas heteropolyacids catalyzed the reaction in the absence of butenes. This revised version was published online in June 2006 with corrections to the Cover Date.     

Recent topics in heterogeneous catalysis of heteropolyacids

First, the state of the art of the catalyst design based on heteropoly compounds is briefly overviewed. Then, selected topics of solid heteropoly catalysts, that is, the selective oxidation of isobutyric acid and isobutane over molybdovanadophosphoric acids, the methyl t-butyl ether synthesis in pseudoliquid of heteropolyacids, and the shape-selective and bifunctional (combined with noble metals) acid catalysis of cesium and ammonium salts of tungstophosphoric acid are described based on the recent studies from our laboratory.     

Effect of water on silica-supported phosphotungstic acid catalysts for 1-butene double bond shift and alkane skeletal isomerization

The thermal stability, acidity, catalytic activity and regenerability of silica-supported phosphotungstic acid were evaluated in reference to the bulk solid acid. Samples were prepared with 5, 10, and 25 wt.% heteropolyacid (HPA) on fumed silica to examine the effect of loading on the properties of supported acid catalysts. X-ray absorption spectroscopy indicated that the supported heteropolyacids did not completely decompose when heated to 573 K. The catalytic activity of both bulk and supported HPAs for double bond shift and skeletal isomerization of light hydrocarbons decreased with increasing pretreatment temperatures, which suggests that the level of hydration is critical for acid catalysis. After pretreatment at 573 K, a well dispersed sample (5 wt.% HPA) catalyzed 1-butene double bond isomerization, a reaction that requires weak acid sites, whereas the sample was inactive for pentane skeletal isomerization, a reaction that requires strong acid sites. Evidently, the well dispersed HPAs did not have sufficient acidity to catalyze pentane isomerization since higher loaded samples were active for the reaction under identical conditions. Ammonia sorption microcalorimetry results correlated well with reactivity, revealing that 5 wt.% HPA on silica had the lowest heat of ammonia sorption, while a 25 wt.% sample had initial heats near that of bulk heteropolyacid (150 kJ mol⁻¹). Treatment of the catalysts with water at mild conditions recovered activity for the bulk and supported heteropolyacids for the 1-butene and pentane isomerization reactions whereas treatment in air or N₂O was ineffective. These findings suggest that water treatment regenerates acid sites by rehydrating partially decomposed Keggin units. Results from in situ UV–VIS spectroscopy of the catalyst samples support the above conclusion.     

A new and efficient catalytic system for synthesis of diphenyl carbonate with W–Mo-heteropolyacids as a cocatalyst

A new catalytic system, which consists of Pd(OAc)₂ as the catalyst and W–Mo-containing heteropolyacids (HPAs)/Mn(OAc)₂ as the bicomponent cocatalysts, has been found to be very efficient in the oxidative carbonylation of phenol to diphenyl carbonate at low pressure in the absence of solvent. The efficiency of the catalytic system is dependent on the ratio of W/Mo in the HPAs, being best in a ratio of 6/6. The synergistic effect between W–Mo-containing HPAs and Mn(OAc)₂ has been observed in the catalysis. This revised version was published online in July 2006 with corrections to the Cover Date.     

1,3-二乙酸咪唑磷钨酸盐的制备及其对甲基红的光催化降解性能

采用元素分析和红外光谱对所制磷钨酸1,3-二乙酸咪唑盐催化剂进行表征,考察了光照时间、催化剂用量对光催化降解有机染料甲基红效率的影响. 结果表明,无光催化剂时甲基红可直接光解,完全光解所需时间为220 min;催化剂用量为0.02?0.10 g时,对甲基红光降解效率随催化剂用量增加显著提高;加入0.08 g催化剂后,紫外光照射60 min可使甲基红溶液降解完全,降解效率为未加入催化剂时的3倍.     

规整结构催化剂及反应器研究进展

介绍了一种新颖的规整结构催化剂。它在废气排放处理等气相催化反应中已表现出优于常规催化剂的优良催化性能,在气液固多相催化反应领域的研究也表明它能够应用于更多的催化反应。将这种催化剂和反应器结构特性与常规催化反应中应用的固体催化剂和反应器进行了比较,结果表明它有可能替代浆态床和固定床反应器,具有良好的应用前景。