甲醇碳基化制乙酸

Monsanto公司的甲醇羰基化制乙酸工艺具有甲醇转化率高、产物产率高等优点，但也存在着主催化剂铑价格昂贵、助催化剂碘化物腐蚀设备等缺点。本文重点从催化机理研究方面介绍了国内外对Monsanto技术的最新改进研究工作、英国石油(BP)公司的甲醇羰基化制乙酸铱基催化体系(名为Cativa^TM工艺)，并介绍了无碘化物促进的甲醇羰基化催化体系，分析了不同催化体系的优缺点及研究发展趋势。     

甲醇直接气相羰基化反应动力学

甲醇直接气相羰基化研究 ,是在无任何促进剂下 ,ＣＯ与甲醇直接进行羰基化反应 ,这与目前公认的甲醇必须有碘化物作用下构成催化循环的间接羰化不同 ,在催化理论上有可能提出新的羰基化机理。彭峰等在甲醇直接气相羰基化方面 ,对具有高活性与选择性的非铑非卤素Ｍｏ Ｃ催化剂体系进行了系列研究 ,并取得了较好的实验结果[1～ 5] 。有碘甲烷参与的甲醇羰基化液相或者气相反应 ,大多数文献认为控制步骤是碘化物中Ｃ -Ｉ键的解离及ＣＯ的插入 ,羰基化反应是由一系列平行和连串反应组成的[6～ 8] 。催化剂类型不同得到的动力学参数也不相同 ,难…     

甲醇气相法羰基化合成乙酸的镍催化剂(YhNi)的研究

本文报导了一种新型的甲醇羰基化生产乙酸的镍催化剂.由于选用了由聚偏二氯乙烯热裂解制得的特殊碳化物为载体,所以该催化剂有大比表面积,孔径分布均匀,并有优良的热稳定性和机械强度,其催化甲醇羰基化的速率在相对温和的条件下达到582克乙酸/克镍/时,高于文献报导的镍金属催化剂.     

金属盐添加剂对甲醇羰基化反应的助催化研究

以[Rh(CO)2Cl]2为催化剂,以Sn、Pb、Cr、Zr金属盐作为添加剂,在催化甲醇羰基化制乙酸的反应中系统考察了不同添加剂对反应的影响.试验证明,含有添加剂的反应体系具有更高的催化活性和选择性,其中乙酸的时空收率最高达到40mol/(L·h)以上.     

铑络合物催化剂的稳定性研究

甲醇低压羰基合成制醋酸的催化剂包括主催化剂铑化合物和助剂碘化物两种组分.溶于醋酸和水的混合溶剂的RhCl_3-CH_3I均相体系对甲醇羰基化反应具有很高的催化活性,但稳定性差,特别是在常压下分离产物时,容易发生催化剂的分解.本工作结合甲醇羰基化反应,研究了铑络合物催化剂的分解作用规律和添加剂对络合物的稳定作用.     

高分子镍催化剂催化甲醇羰基化制备乙酸

高分子镍催化剂催化甲醇羰基化制备乙酸潘平来，柳忠阳，黄茂开，袁国卿（中国科学院化学研究所北京１０００８０）关键词高分子镍催化剂，羰基化醇类的谈基化反应早在５０年代初就开始研究，ＲｅＰＰｌｅ［Ｕ等人研究发现周期表中第八族金属元素的藏基化物对甲醇谈基化有...     

甲醇气相羰基化制备乙酸的钴催化剂(YSCo)的研究

甲醇气相羰基化制备乙酸的钴催化剂（ＹＳＣｏ）的研究潘平来，柳忠阳，黄茂开，袁国卿（中国科学院化学研究所，北京１０００８０）关键词甲醇，羰基化，乙酸，钴催化剂通过甲醇羰基化制备乙酸是目前乙酸工业最先进的技术路线．该法与乙烯和乙醇氧化法相比较，无论从原料...     

乙醇直接气相羰基化新催化剂

醇的羰基化合成是极有工业价值的过程 ,也是绿色化学中提倡的原子经济性反应 [1] .甲醇均相羰基化合成醋酸是 Monsanto公司成功开发应用的典范 [2 ] ,而乙醇羰基化合成丙酸或丙酸乙酯的研究尤其重要 .前文对一种性能优良的负载型 Ni系催化剂用于乙醇常压气相羰基化合成丙酸及其酯作了报道 [3,4] ,与均相羰基化相比 ,该反应具有条件温和 ,不使用贵金属铑 ,催化剂与产物不存在分离上的困难等优点 ,但反应体系仍需使用卤化物作促进剂 .由于碘乙烷的存在 ,反应系统设备腐蚀严重 (有 HI生成 ) ,产物分离精制复杂 .目前 ,醇的均相羰基化及多相羰…     

丙烯酰胺—丙烯酸甲酯共聚物铑配合物催化甲醇羰基化反应制备乙酸

合成了一系列丙烯酰胺－丙烯酸甲酯共聚物铑配合物,采用Ｘ－射线光电子能谱（ＸＰＳ）和ＩＲ光谱研究了其中存在的配位结构,通过催化甲醇羰基化反应制备乙酸,考察了它们作为该反应的催化剂的性能,并证明了该催化剂体系具有高活性,高选择性和低腐蚀性。     

甲醇羰基化制醋酸铱基催化剂的研究

摘要 醋酸是一种重要的化工原料，甲醇羰基化是目前生产醋酸的主要方法， 铱基催化剂是最有发展前景的甲醇羰基化反应制备醋酸的催化剂。介绍了铱基催化 剂体系的催化机理、速度影响因素，并与铑基催化剂进行了比较．     

二氧化碳与环氧化物共聚催化剂研究进展

二氧化碳是主要的温室气体,也是最丰富的C1资源.利用二氧化碳与环氧化物共聚生成可生物降解的聚碳酸酯是目前研究的热点之一.就目前的研究情况而言,二氧化碳与环氧化物共聚反应存在的主要问题是催化效率低、催化剂成本高、反应条件苛刻、共聚物产率较低以及催化剂分离复杂等.我们分类综述了二氧化碳与环氧化物共聚的新型催化体系,并探讨了各类催化体系的优缺点,对二氧化碳的资源化利用具有重要的应用价值.     

Synthesis of micronized CaO assisted by NH4HCO3 with Ca(OH)2 and its application in heterogeneously catalyzing transesterification reaction for producing biodiesel

Micronized CaO with pores was synthesized by calcining the reaction product CaCO₃ from NH₄HCO₃ and Ca(OH)₂. Scanning electron microscopy, X‐ray diffraction, energy dispersive X‐ray spectroscopy, X‐ray fluorescence, Fourier transform infrared spectroscopy, and Brunauer–Emmett–Teller analysis were used to characterize CaO, which confirmed that after calcining at 800°C for 2 hr, CaCO₃ was completely converted into porous micronized CaO with a surface area of about 7.295 m²/g and a particle size of 0.5–1.5 μm. The porous CaO microparticles were used as heterogeneous catalysts for producing biodiesel from transesterification of soybean oil and methanol. The influences of reaction time, calcined temperature, and reusability of CaO were explored. The experiments showed that CaO has high catalytic activity for transesterification reaction, and the yield of biodiesel reaches more than 98% under the conditions of methanol/oil mole ratio of 9, and the catalyst amount (catalyst/oil) of 3% after reaction for 2.5 hr. The CaO catalyst can be recycled easily and it also has the advantage of low pollution. Simple synthetic route, low cost, high catalytic activity, good reusability, and great potential for industrialization are the advantages of the porous micronized CaO catalyst that was proposed in this work.     

Construction of polymeric Cu(I) N-heterocyclic carbene complex utilizing terpyridine-Fe(II) as linkers: formation of an efficient and recyclable catalyst

A metal-coordination-driven self-assembly using the predesigned building block has been developed. Herein, the catalytic active NHC–Cu(I) units were introduced into the terpyridine metal coordination polymers. The self-assembled architecture, as a heterogeneous catalyst, was successfully used to catalyze the A³-coupling reaction of aldehyde, alkyne, and amine and Huisgen 1,3-dipolar cycloaddition reaction of azide and alkyne in high yields.     

Silica iminopyridine-functionalized nanomaghemite enhances the oxygenation activity and durability of simple Co(II) salophen complex

A novel magnetically recoverable catalyst was produced by coordinative attachment of Co(II) salophen complex to silica iminopyridine (SIPy)-functionalized-γ-Fe₂O₃ magnetic nanoparticles (SMNP@SIPy/Co(II) salophen). The vibration spectra and compositional data provided sufficient evidences for the structural integrity of as-prepared organic–inorganic nanohybrid. The magnetic nanocatalyst proved to be an efficient and selective heterogeneous catalyst for oxidation of different benzylic alcohols and featured higher catalytic activity and stability than that of homogenous counterpart. A TOF of 151 h⁻¹ and TON of more than 322 were obtained for oxidation of 4-cholrobenzyl alcohol in this catalytic system. The supported catalyst could easily be recovered from the reaction mixture by an external magnetic field and reused for subsequent experiments with consistent catalytic activity.     

Single and binary catalyst systems based on nickel and palladium in polymerization of ethylene

The catalyst (N,N‐bis(2,6‐dibenzhydryl‐4‐ethoxyphenyl)butane‐2,3‐diimine)nickel dibromide, a late transition metal catalyst, was prepared and used in ethylene polymerization. The effects of reaction parameters such as polymerization temperature, co‐catalyst to catalyst molar ratio and monomer pressure on the polymerization were investigated. The α‐diimine nickel‐based catalyst was demonstrated to be thermally robust at a temperature as high as 90 °C. The highest activity of the catalyst (494 kg polyethylene (mol cat)^?1 h^?1) was obtained at [Al]/[Ni] = 600:1, temperature of 90 °C and pressure of 5 bar. In addition, the performance of a binary catalyst using nickel‐ and palladium‐based complexes was compared with that of the corresponding individual catalytic systems in ethylene polymerization. In a study of the catalyst systems, the average molecular weight and molecular weight distribution for the binary polymerization were between those for the individual catalytic polymerizations; however, the binary catalyst activity was lower than that of the two individual ones. The obtained polyethylenes had high molecular weights in the region of 10⁵ g mol^?1. Gel permeation chromatography analysis showed a narrow molecular weight distribution of 1.44 for the nickel‐based catalyst and 1.61 for the binary catalyst system. The branching density of the polyethylenes generated using the binary catalytic system (30 branches/1000 C) was lower than that generated using the nickel‐based catalyst (51/1000 C). X‐ray diffraction study of the polymer chains showed higher crystallinity with lower branching of the polymer obtained. Also Fourier transform infrared spectra confirmed that all obtained polymers were low‐density polyethylene.     

低温甲醇液相合成催化剂及工艺的研究进展

本文综述了低温液相合成甲醇的发展历史、研究现状和目前存在的关键技术问题。重点讨论了催化剂体系和活性中心、催化反应过程和工艺、反应机理和失活机理以及催化剂循环再生的研究。与传统的甲醇合成方法比较, 液相低温甲醇直接合成方法具有单程转化率高(90% 以上) , 生产成本低, 产品品质优, 反应条件温和等优点。共引用参考文献36 篇。     

Rapid Suzuki‐Miyaura cross‐coupling reaction catalyzed by zirconium carboxyphosphonate supported mixed valent Pd(0)/Pd(II) catalyst

Mixed valent Pd(0)/Pd(II) nano‐sized aggregates supported onto a chemically robust layered zirconium carboxyphosphonate framework is prepared and its catalytic activity in Suzuki‐Miyaura cross coupling reaction is explored. The exceptionally high catalytic efficacy of the heterogeneous catalyst in Suzuki‐Miyaura cross coupling reaction is signified by remarkably short reaction time 2 minutes and high turnover frequency of 1.3 x 10⁴ hr^?1. The catalyst can be recycled several times without significant loss of catalytic efficacy, while spectroscopic, structural and microscopic investigations suggest the integrity of the catalyst even after fifth catalytic cycle. The unique ability of the zirconium carboxyphosphonate framework to interact strongly with palladium in dual Pd(0)/Pd(II) oxidation states has been attributed to this remarkable augmentation of catalytic efficacy.     

APUSM technology for the production of BTX and LPG from pyrolysis gasoline using metal promoted zeolite catalyst

SK Corporation developed an advanced pyrolysis gasoline (pygas) upgrading (APU^SM) technology based on a catalytic process for producing valuable benzene, toluene and xylenes (BTX) and liquefied petroleum gas (LPG) from pygas containing aromatics and non-aromatic hydrocarbons. Hydrodealkylation of heavy aromatics and hydrocracking of non-aromatic hydrocarbons occurred with facility in the conversion of pygas over a proprietary catalyst, metal promoted zeolite. This catalytic process produced benzene and toluene with high purity corresponding to chemical grade while giving mixed xylenes with reduced ethylbenzene. In the present study, we described novel features of the APU^SM technology in terms of the process and catalyst. The influence of the process conditions was also examined. This technology has been commercially proven, and hence is available for licensing through Axens, which is a major engineering and licensing company.     

Highly efficient protection of alcohols and phenols catalysed by tin porphyrin supported on MIL‐101

The catalytic activity of 5,10,15,20‐tetrakis(4‐aminophenyl)porphyrinatotin(IV) trifluoromethanesulfonate, [Sn^IV(TNH₂PP)(OTf)₂], supported on chloromethylated MIL‐101, was investigated in the trimethylsilylation of alcohols and phenols with hexamethyldisilazane (HMDS) and also their tetrahydropyranylation with 3,4‐dihydro‐2H‐pyran. Excellent yields, mild reaction conditions, short reaction times and reusability of the catalyst without significant decrease in its initial activity are noteworthy advantages of this supported catalyst. Copyright © 2015 John Wiley & Sons, Ltd.     

酯交换法合成碳酸甲乙酯研究进展

碳酸甲乙酯(EMC)具有诸多优异的物理和化学性能,作为锂电池电解液溶剂已经被行业广泛认可,酯交换法是中国目前工业生产EMC的主要方法。本研究系统综述了碳酸酯交换反应热力学、动力学、均相及非均相催化剂、反应机理及反应工艺等方面的研究,重点评述了近五年酯交换法制备EMC的最新进展。均相催化剂中以pK_b值(碱度系数)为标准讨论了可溶碱类催化剂碱强度和催化效率之间的关系,探究了咪唑类离子液体阴、阳离子结构对反应效果的影响规律。针对工业上普遍采用的甲醇钠催化剂,描述了其失活现象并阐述了失活机理。详细比较和讨论了非均相催化剂的制备方法、表面酸碱性与催化效率之间的关系,综合评价了不同类别的催化剂催化酯交换反应的优缺点。着眼绿色、高纯、低成本EMC合成技术,高效固体碱催化剂和涉及气、液、固三相的催化精馏技术是今后开发的重点和发展方向。