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以CO2与环氧乙(丙)烷合成碳酸乙(丙)烯酯的反应为主要研究对象,对应用于环氧烷和CO2反应制备环状碳酸酯的催化剂进行比较,并对未来的发展方向进行了预测.结果发现,均相催化剂,特别是金属配合物催化剂,用于CO2和环氧烷合成环状碳酸酯反应的催化活性和选择性通常比较高,但均相催化剂与产物分离困难.与均相催化剂相比,多相催化剂易于和产物分离.但普通的多相催化剂,如金属氧化物催化剂和碱金属分子筛催化剂的催化活性较差,反应条件苛刻.将均相催化剂固载化形成具有高活性、高选择性和高稳定性的多相催化剂将是未来的发展方向. 相似文献
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基于“可持续发展”和“绿色化学”的概念,近年来CO2的捕获、储存及资源化利用在工业上和学术上一直备受关注。通过具有100%原子经济性特点的CO2与环氧化物环加成反应合成五元环状碳酸酯是最有前景的方法之一。基于均相催化剂的设计思想与方法,以CO2和环氧化物的活化本质出发,从催化剂结构的角度综述了均相体系中酸碱协同催化CO2与环氧化物环加成反应合成环状碳酸酯的研究进展,包括简单二元催化体系、功能型一元催化体系和金属配合物催化体系等。 相似文献
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环氧环己烷与二氧化碳合成碳酸环己烯酯的化学反应动力学 总被引:1,自引:0,他引:1
引言由于CO2排放量的急剧增加,“温室效应”已成为当今世界性的难题,固定CO2并综合利用CO2的研究显得越来越重要。CO2和环氧化合物经过环加成反应制备环状碳酸酯的工艺路线,为固定和利用CO2提供了一条有效途径。环状碳酸酯不仅是一种性能优良的高沸点、高极性的有机溶剂,而且在 相似文献
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合成了咪唑离子液体功能化salen Mn配合物(IL-salen Mn),并作为催化剂应用于苯乙烯与CO2一锅合成碳酸苯乙烯酯反应中.以尿素过氧化氢(UHP)为氧化剂、吡啶氮氧化物(PyNO)为助剂,催化苯乙烯高效制备环氧苯乙烷,继而催化环氧苯乙烷与CO2发生环加成反应合成碳酸苯乙烯酯.考察了催化剂种类和用量、助剂用量、氧化剂种类和用量、反应时间、反应温度及CO2压力对上述反应的影响.结果表明,当催化剂IL-salen Mn用量为苯乙烯物质的量的8%、n(苯乙烯):n(UHP):n(PyNO)=1.0:3.0:0.2、环氧化反应温度和时间分别为30℃和5 h、环加成反应温度和时间分别为80℃和12 h、CO2压力为1.0 MPa时,苯乙烯的转化率为90%,碳酸苯乙烯酯收率达到32%.结合前期研究与反应时间动力学结果,推测了该一锅反应的可能机理. 相似文献
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合成了咪唑离子液体功能化salen Mn配合物(IL-salen Mn),并作为催化剂应用于苯乙烯与CO2一锅合成碳酸苯乙烯酯反应中.以尿素过氧化氢(UHP)为氧化剂、吡啶氮氧化物(PyNO)为助剂,催化苯乙烯高效制备环氧苯乙烷,继而催化环氧苯乙烷与CO2发生环加成反应合成碳酸苯乙烯酯.考察了催化剂种类和用量、助剂用量、氧化剂种类和用量、反应时间、反应温度及CO2压力对上述反应的影响.结果表明,当催化剂IL-salen Mn用量为苯乙烯物质的量的8%、n(苯乙烯):n(UHP):n(PyNO)=1.0:3.0:0.2、环氧化反应温度和时间分别为30℃和5 h、环加成反应温度和时间分别为80℃和12 h、CO2压力为1.0 MPa时,苯乙烯的转化率为90%,碳酸苯乙烯酯收率达到32%.结合前期研究与反应时间动力学结果,推测了该一锅反应的可能机理. 相似文献
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合成了咪唑离子液体功能化salen Mn配合物(IL-salen Mn),并作为催化剂应用于苯乙烯与CO2一锅合成碳酸苯乙烯酯反应中.以尿素过氧化氢(UHP)为氧化剂、吡啶氮氧化物(PyNO)为助剂,催化苯乙烯高效制备环氧苯乙烷,继而催化环氧苯乙烷与CO2发生环加成反应合成碳酸苯乙烯酯.考察了催化剂种类和用量、助剂用量、氧化剂种类和用量、反应时间、反应温度及CO2压力对上述反应的影响.结果表明,当催化剂IL-salen Mn用量为苯乙烯物质的量的8%、n(苯乙烯):n(UHP):n(PyNO)=1.0:3.0:0.2、环氧化反应温度和时间分别为30℃和5 h、环加成反应温度和时间分别为80℃和12 h、CO2压力为1.0 MPa时,苯乙烯的转化率为90%,碳酸苯乙烯酯收率达到32%.结合前期研究与反应时间动力学结果,推测了该一锅反应的可能机理. 相似文献
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酯交换法合成碳酸二甲酯研究进展 总被引:2,自引:0,他引:2
从催化剂体系和反应条件等方面,综述了酯交换法合成碳酸二甲酯的研究新进展。介绍了硫酸二甲酯法、环烷基碳酸酯法和甲醇、环氧烷、CO2一步合成法,并评价所用催化剂的性能,分析了这些合成方法的优缺点。 相似文献
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A novel catalytic application of titanosilicate molecular sieves (TS-1 and TiMCM-41), in the synthesis of polycarbonate precursors like cyclic carbonates and dimethyl and diphenyl carbonates, avoiding toxic chemicals like phosgene or CO, is reported. Cyclic carbonates were prepared, over TS-1 and TiMCM-41, in high yields, by cycloaddition of CO2 to epoxides, like epichlorohydrin, propylene oxide and styrene oxide, at low temperatures and pressures. Further, transesterification of the cyclic carbonates with methanol and phenol, over TiMCM-41, yielded other polycarbonate precursors like dimethyl carbonate (DMC) and diphenyl carbonate (DPC). The cyclic carbonates could also be synthesized from the olefins in the same reactor by reacting the olefins, in the presence of TiMCM-41, with a mixture of an epoxidizing agent (like H2O2 or tert-butyl hydroperoxide) and CO2. 相似文献
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Yogesh P. PATIL Pawan J. TAMBADE Sachin R. JAGTAP Bhalchandra M. BHANAGE 《Frontiers of Chemical Science and Engineering》2010,4(2):213
The syntheses of carbon dioxide (CO2) based industrially important chemicals have gained considerable interest in view of the sustainable chemistry and “green chemistry” concepts. In this review, recent developments in the chemical fixation of CO2 to valuable chemicals are discussed. The synthesis of five-member cyclic carbonates via, cycloaddition of CO2 to epoxides is one of the promising reactions replacing the existing poisonous phosgene-based synthetic route. This review focuses on the synthesis of cyclic carbonates, vinyl carbamates, and quinazoline-2,4(1H,3H)-diones via reaction of CO2 and epoxide, amines/phenyl acetylene, 2-aminobenzinitrile and other chemicals. Direct synthesis of dimethyl carbonate, 1,3-disubstituted urea and 2-oxazolidinones/2-imidazolidinones have limitations at present because of the reaction equilibrium and chemical inertness of CO2. The preferred alternatives for their synthesis like transesterification of ethylene carbonate with methanol, transamination of ethylene carbonate with primary amine and transamination reaction of ethylene carbonate with diamines/β-aminoalcohols are discussed. These methodologies offer marked improvements for greener chemical fixation of CO2 in to industrially important chemicals. 相似文献
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Chemical fixation of CO2 into useful organic compounds has been attracting much attention from the viewpoint of CO2 emission reduction and energy structure reformation. A useful and widely investigated chemical utilization of CO2 is the cycloaddition of CO2 to epoxides for the synthesis of cyclic carbonates. Efforts have been paid to the design and preparation of various catalyst systems that are active and selective to the production of the desired products under mild conditions and in green processes. This article is to review the current state of the catalyst development and the experimental and theoretical analysis of reaction mechanism for the cyclic carbonate synthesis from epoxides, one of currently important reactions involving CO2 as a reactant with 100% atom economy. Particular attention is given to the catalysis of multifunctional catalyst systems such as metal- and hydrogen-bond donor (HBD)-based catalysts. 相似文献
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二氧化碳(CO2)是主要的温室气体,同时也是一种廉价、无毒且可再生的一碳资源,因此将CO2转化为有价值的精细化学品可有效减缓气候变化、助力实现碳中和。CO2与环氧化物的环加成反应具有高原子经济、高选择性、低污染等优点,其产物环状碳酸酯可作为锂离子电池电解质、聚合物材料前体以及精细化学品中间体,应用前景广阔。氧化物因具有结构多样、可调性强等优点在CO2与环氧化物的环加成反应中的应用引起了广泛的关注。文章综述了两种典型且成本低廉、易于规模化生产的氧化物——金属氧化物与分子筛催化CO2与环氧化物的环加成反应的研究进展,重点分析了反应机理以及催化剂的应用。今后的研究重点是高性能无助剂的非均相催化剂的开发以及催化机理的探究。 相似文献
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Weili DAI Chaktong AU Shenglian LUO Shuangfeng YIN 《Frontiers of Chemical Science and Engineering》2010,4(2):163
In this article, we present our research results on chemical fixation of CO2 using organobismuth compounds. We fabricated bismuth biphenoate complex, Zn-Mg-Al composite oxides, and SBA-15 or Al-SBA-15 immobilized hydroxyl ionic liquid for CO2 cycloaddition onto epoxides. The hypervalent bismuth compounds show good ability for association and dissociation with CO2. The bismuth biphenolate complexes are catalytically effective for the cycloaddition reaction. The heterogeneous catalysts, viz. Zn-Mg-Al oxides and SBA-15 or Al-SBA-15 immobilized ionic liquid, are efficient for the synthesis of cyclic carbonate from CO2 and epoxide. It is found that the presence of a trace amount of water can improve the catalytic activity of the immobilized ionic liquid. 相似文献
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Yogesh P. Patil Pawan J. Tambade Sachin R. Jagtap Bhalchandra M. Bhanage 《Frontiers of Chemical Engineering in China》2010,4(2):213-235
The syntheses of carbon dioxide (CO2) based industrially important chemicals have gained considerable interest in view of the sustainable chemistry and “green
chemistry” concepts. In this review, recent developments in the chemical fixation of CO2 to valuable chemicals are discussed. The synthesis of five-member cyclic carbonates via, cycloaddition of CO2 to epoxides is one of the promising reactions replacing the existing poisonous phosgene-based synthetic route. This review
focuses on the synthesis of cyclic carbonates, vinyl carbamates, and quinazoline-2,4(1H,3H)-diones via reaction of CO2 and epoxide, amines/phenyl acetylene, 2-aminobenzinitrile and other chemicals. Direct synthesis of dimethyl carbonate, 1,3-disubstituted
urea and 2-oxazolidinones/2-imidazolidinones have limitations at present because of the reaction equilibrium and chemical
inertness of CO2. The preferred alternatives for their synthesis like transesterification of ethylene carbonate with methanol, transamination
of ethylene carbonate with primary amine and transamination reaction of ethylene carbonate with diamines/β-aminoalcohols are discussed. These methodologies offer marked improvements for greener chemical fixation of CO2 in to industrially important chemicals. 相似文献
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Non-isocyanate polyurethanes (NIPUs) based on cyclic carbonate-amine chemistry are an emerging area for polymer synthesis and is being extensively studied for various applications. A successful utilization of this technology can eliminate many of the issues associated with conventional polyurethane chemistry. While these polymers have not yet achieved commercial significance, research is being devoted to methods for synthesizing polymers or oligomers containing cyclic carbonate groups as well as studying their applications in thermoplastic and thermosetting systems. 相似文献