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水滑石及类水滑石材料的合成及应用新进展 总被引:13,自引:0,他引:13
水滑石及类水滑石材料具有很好的热稳定性和较大的比表面积,可以作为催化剂或催化剂载体。介绍了水滑石及类水滑石材料的合成方法以及作为催化剂、添加剂、吸附剂在有机合成反应、石油化学、塑料工业、水处理等方面的应用。 相似文献
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以过氧化钼为催化活性中心,采用后修饰法制备了以金属有机框架为载体的UiO-67-MoO(O2)2催化剂,并利用XRD、FT-IR、XPS、HRTEM和N2物理吸附等表征手段对该催化剂进行分析;研究了以过氧化氢异丙苯为氧化剂氧化丙烯制备环氧丙烷的反应,重点考察了反应溶剂和反应温度对丙烯环氧化反应的影响。结果表明,环氧丙烷的产率在极性小的反应溶剂中较高。以过氧化氢异丙苯为氧化剂,二氯甲烷为溶剂,在丙烯压力为0. 6 MPa、反应温度为80℃、反应时间为6 h的条件下,过氧化氢异丙苯的转化率为52. 2%,环氧丙烷的产率为20. 9%,且反应后的催化剂骨架仍保持完整。 相似文献
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近年来有机合成反应中水滑石类化合物作为新型催化剂发展迅速。本文介绍了水滑石类化合物的结构、性能及用途,重点介绍其催化性能。 相似文献
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采用变温水热合成方法制备了钛硅钒分子筛TSV。以此分子筛为催化剂,在无溶剂的条件下,对甲基氯丙烯与过氧化氢催化环氧化反应进行了研究,制得甲基环氧氯丙烷。利用正交实验,研究了反应温度、反应时间、催化剂用量及反应物摩尔比四个因素对甲基氯丙烯的转化率与甲基环氧氯丙烷的选择性的影响,分析甲基氯丙烯的转化率与甲基环氧氯丙烷的选择性,确定了较佳的反应条件,并进行了催化剂重复使用实验。实验结果表明所制备的催化剂具有较高的稳定性。 相似文献
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《云南化工》2017,(5):16-19
采用双滴共沉淀法合成Mg Al二元水滑石及其复合氧化物、Cu Mg Al三元水滑石及其复合氧化物,并对其进行化学分析。将铁作为潜在的磁性物种制备铁氧体,合成不同Mg/Fe(Ⅱ)摩尔比的磁性纳米Mg Al水滑石及其复合氧化物。通过原子力显微镜、红外光谱仪以及热重-差热分析仪对各类产物进行表征,并对磁性水滑石进行磁学性能的测试。结果表明,样品中Cu、Mg、Al的质量分数与化学式计算出的含量基本一致。原子力显微镜观测到各类样品的粒径均在20~60nm之间,且颗粒分布较均匀;IR分析和DTA分析表明:各类产物具有水滑石类化合物的结构特征。磁学性能测试表明,合成出的磁性水滑石具有一定的磁性。 相似文献
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以磷钨杂多酸季铵盐为催化剂,过氧化氢为氧源,在添加相转移试剂形成的两相体系中催化氧化双环戊二烯(DCPD)合成了二氧化双环戊二烯(ERL-4207),考察了催化剂、络合剂、pH调节剂、反应温度及反应时间等条件对环氧化反应的影响。优化反应条件为:n(Cat)∶n(KH2PO4)=100∶25,络合剂为乙二胺四乙酸,n(Cat)∶n(DCPD)∶n(H2O2)=5.68∶1000∶2600,70%(m/m)过氧化氢为氧源,反应温度30℃,反应时间5h。在此条件下,反应物的转化率可达到99.99%,ERL-4207的选择性达到84.26%。无溶剂法合成ERL-4207是一条绿色环保的合成路线。 相似文献
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Kristin Schrder Stephan Enthaler Benoît Join Kathrin Junge Matthias Beller 《Advanced Synthesis \u0026amp; Catalysis》2010,352(10):1771-1778
The combination of iron(III) chloride, pyridine‐2,6‐dicarboxylic acid and formamidine ligands allows for the epoxidation of styrenes and conjugated dienes in excellent chemoselectivity and yields. 相似文献
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Titanium-containing catalysts have been prepared by two different post-synthesis methods using activated carbon and carbon-silica composite as catalyst supports. They have been applied to the liquid-phase epoxidation of cyclohexene with tert-butyl hydroperoxide (TBHP) and H2O2. The carbon-silica composite catalyst showed a high conversion and selectivity to epoxide compared to the Ti-carbon catalyst and silica-based catalysts for the cyclohexene epoxidation with H2O2. The highest values of cyclohexene conversion and epoxide selectivity were obtained with the carbon-silica composite catalyst having a titanium content of 3 wt%. 相似文献
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In this review the state-of-the-art of catalytic processes known today for selective epoxidations using aqueous H2O2 as the oxidant is presented. Recent achievements from our laboratories on the development of catalysts for epoxidations with H2O2 are given as well. For all systems their viability for application in green catalytic processes is evaluated, based on selectivity of the reaction, turnover frequency, substrate scope and solvent needed. 相似文献
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Epoxidation of propylene and direct synthesis of hydrogen peroxide by hydrogen and oxygen 总被引:2,自引:0,他引:2
The autoreduction of palladium–platinum-containing titanium silicalite leads to an effective catalyst for the epoxidation of propylene to propylene oxide by O2 in the presence of H2. The one-pot reaction is favoured compared to the two-step reaction path. 相似文献
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Marco Colladon Alessandro Scarso Giorgio Strukul 《Advanced Synthesis \u0026amp; Catalysis》2007,349(6):797-801
Remarkable improvements in enantioselectivity as well as recycle were observed in the catalytic asymmetric epoxidation of terminal alkenes with a chiral, electron‐poor platinum(II ) catalyst with hydrogen peroxide as terminal oxidant in water‐surfactant media. 相似文献
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Keigo Kamata Kazuya Yamaguchi Shiro Hikichi Noritaka Mizuno 《Advanced Synthesis \u0026amp; Catalysis》2003,345(11):1193-1196
A dinuclear peroxotungstate, K2[{W(O)(O2)2(H2O)}2(μ‐O)]⋅2 H2O, exhibits high catalytic performance for the epoxidation of various allylic alcohols with only one equivalent of hydrogen peroxide at 305 K in water solvent. The effectiveness of this system is evidenced by high chemo‐, regio‐, and diastereoselectivity, and stereospecificity for the epoxidation of allylic alcohols. Furthermore, products/catalyst separation can be easily carried out by simple extraction and the catalyst recovered can be reused with the maintenance of the catalytic performance. 相似文献