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《硅酸盐学报》2015,(9)
以1-辛烯和三乙氧基氢硅烷为原料,在Karetedt催化剂及酸促进剂作用下,进行硅氢加成反应合成正辛基三乙氧基硅烷,研究了反应温度、滴加方式、催化剂用量、促进剂用量、滴加时间等工艺条件对原料烯烃异构化及产品收率的影响。利用核磁共振(1HNMR)对烯烃异构体和目标产品正辛基三乙氧基硅烷进行结构鉴定,利用气相色谱对反应后液体进行进一步定性、定量检测。结果表明:以三乙氧基氢硅烷为滴加剂,反应温度在90~100℃之间,催化剂用量0.000 15%(质量分数)~0.000 20%,促进剂用量为0.15%~0.20%,滴加时间1.5 h为正辛基三乙氧基硅烷合成的最佳工艺条件。在此条件下,反应后液体中异构烯烃含量为1.34%,产品含量为92.48%。 相似文献
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具有多齿配位基的硅单体 总被引:2,自引:0,他引:2
通过含多齿配位基的烯烃与三乙氧基硅烷的硅氢加成反应、或γ-巯丙基三甲氧基硅烷与β-氯乙基硫醚的缩合反应,合成了5种新型具有多齿配位基的硅单体。 相似文献
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三硅氧烷咪唑离子液体表面活性剂的合成与表面活性 总被引:1,自引:0,他引:1
以氯丙基甲基二甲氧基硅烷和六甲基二硅氧烷为原料,在浓硫酸催化下合成了氯丙基三硅氧烷,再与1-甲基咪唑进行季铵化反应,制备了三硅氧烷咪唑离子液体表面活性剂.用傅里叶红外光谱仪以及氢谱和碳谱核磁共振仪表征了产物的结构;并对其临界胶束浓度(cmc)及表面张力(γ)进行了测定.结果表明,与长链烷基咪唑类离子液体表面活性剂相比,三硅氧烷咪唑离子液体表面活性剂具有更好的表面活性,其cmc为15.5 mmol/L,γcmc为24.0 mN/m. 相似文献
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γ-巯丙基三乙氧基硅烷用气相法二氧化硅固载,再与氯亚铂酸钾作用,合成了聚γ-巯丙基奎氧烷铂(Ⅱ)配合物。研究了该了该梧全物对烯烃与三乙氧基硅烷的硅氢加成反应的催化特性。 相似文献
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在甲苯/离子液体两相催化体系中,以三苯基膦和三氯化钌活化生成的配合物为催化剂,研究了顺酐选择性加氢生成四氢呋喃的反应,考察了离子液体、反应时间、反应温度、反应压力、顺酐与催化剂物质的量比以及离子液体用量对加氢反应的影响,同时考察了离子液体的循环使用。在453 K、12 h、4 MPa和n(PPh3)∶n(RuCl3)=3∶1的条件下,反应的转化率和选择性分别为100%和962%。由于催化剂“负载”于离子液体中且产物不溶于离子液体,通过简单的相分离即可分离催化剂和产物。离子液体催化体系重复使用5次后,其催化活性基本不变。 相似文献
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SO3H-功能化季铵盐离子液体催化酯交换制备生物柴油 总被引:1,自引:0,他引:1
采用两步合成法制备了4种SO3H-功能化季铵盐离子液体,红外与核磁共振光谱表征结果表明,其结构符合理论结构特点. 热稳定性分析表明,其分解温度都在200℃以上,均可作为制备生物柴油的催化剂. 将这4种离子液体用于催化制备生物柴油,其催化活性主要与其阴离子的结构有关,[n-But3N(CH2)3SO3H][CH3SO3]的催化活性最好. 甲醇:三油酸甘油酯摩尔比为12:1、催化剂用量7%(w)、在65℃下反应24 h时,油酸甲酯产率最高(89.65%). 催化剂重复使用性能良好. 相似文献
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Radioactive high-level liquid wastes contain significant quantities of platinum group metals (PGM) such as palladium [Pd(II)],
rhodium [Rh(III)] and ruthenium [Ru(III)]. The PGM are produced as fission products in a nuclear reactor. In this study, batch
and column experiments were carried out to investigate the ion exchange characteristics of Rh(III) and Ru(III) including the
effects of the ionic group of ion exchangers, solution temperature, and the concentration of nitric acid by various ion exchangers
such as IRN 78 and Dowex 1x 8; the elution characteristics of Rh(III) and Ru(III) by various eluents were also investigated.
Anion exchangers such as Dowex 1x 8 with the ionic group of quaternary methyl ammonium had a higher capacity than anion exchanger
such as IRN 78 with amine group for the adsorption of Rh(III) and Ru(III) from a simulated liquid waste. The optimal nitric
acid concentration for the adsorption of Rh(III) and Ru(III) by anion exchangers was shown to be about 3 M and 2–3 M, respectively. 相似文献
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考察了碱性离子液体1-乙基-3-甲基咪唑磷酸二乙酯盐{[Em im]+[(EtO)2(PO)O]-}催化一系列醛与活性亚甲基类化合物的Knoevenagel反应,比较了该离子液体在有溶剂存在及无溶剂条件下的催化性能。结果表明,该离子液体在乙醇作溶剂条件下对芳香醛的反应具有较高的催化活性,采用摩尔分数为20%的离子液体来催化该反应,于室温反应即可顺利完成,产率达73.2%~97%,生成相应的取代烯烃化合物。在无溶剂条件下采取机械研磨的方法进行反应,该离子液体表现出更高的催化活性,采用摩尔分数为10%的离子液体进行反应,在1~10 m in即可使产率达90%以上,所得产物均为E式构型。而且在无溶剂条件下,不仅可催化芳香醛的反应,亦可催化脂肪醛的反应。所用离子液体可重复使用,第5次使用时产率仍能达到85.9%。 相似文献
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对几种铑膦络合物催化混合 C8烯烃氢甲酰化反应作了实验研究 ,结果表明 ,在一定反应条件下 ,[Rh( CH3COO) 2 ]2 、Rh( CO) PPh3( acac)和 Rh6 ( CO) 16 均是有效的催化剂前体。配体、铑的浓度及溶剂对催化体系性能影响的实验证明 ,外加 OPPh3、选用适量 Rh浓度及加入二乙二醇二甲醚或四乙二醇二甲醚等溶剂对 C8烯烃氢甲酰化反应生成 C9醛是有利的。实验表明 ,对于 [Rh( CH3COO) 2 ]2 - OPPh3催化体系在 1 40℃及 1 0 .5MPa反应条件下 ,混合 C8烯烃氢甲酰化反应生成 C9醛的收率可达 90 %以上。 相似文献
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An efficient method was investigated for the synthesis of 3‐pentadecylphenyl acrylate (PDPA) via one‐pot reaction of esterification in the presence of an ionic liquid as catalyst. In order to understand the esterification reaction process, a mathematical relationship between the yield of esterification and the process variables was established by employing central composite design. The maximum yield of esterification of 3‐pentadecylphenol (PDP) and acryloyl chloride (AC) catalyzed by imidazole ionic liquid was found to be 85 %. A statistical model predicted that the highest esterification reaction yield would be > 88 % under optimized reaction conditions. The predicted values for optimum process conditions thus obtained were in agreement with the experimental values, thereby indicating the suitability of the model. 相似文献
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合成了6种咪唑型离子液体[C3-8mim]Br/FeCl3,采用红外光谱和拉曼光谱对其进行表征,并考察了离子液体对二苯并噻吩的萃取脱除效果。结果发现,[C3mim]Br/FeCl3的萃取脱硫效果最佳,升高温度和增大剂油比均有利于脱硫率的提高,剂油比1:1(体积比)时,萃取时间达到12 min就可使脱硫率高达92%。且萃取反应完成后,离子液体不做处理继续重复使用,重复使用5次,脱硫率可以达到60%。 相似文献
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Jian-Mei Li Fei-Yang Huang Wei-Zheng Weng Xiao-Qing Pei Chun-Rong Luo Hai-Qiang Lin Chuan-Jing Huang Hui-Lin Wan 《Catalysis Today》2008,131(1-4):179-187
Catalytic performance for partial oxidation of methane (POM) to synthesis gas was studied over the Rh/Al2O3 catalysts with Rh loadings between 0.1 and 3 wt%. It was found that the ignition temperature of POM reaction increased with the decreasing of the Rh loadings in the catalysts. For the POM reaction over the catalysts with high (≥1 wt%) Rh loadings, steady-state reactivity was observed. For the reaction over the catalysts with low (≤0.25 wt%) Rh loadings, however, oscillations in CH4 and reaction products (CO, H2, and CO2) were observed. Comparative studies using H2-TPR, O2-TPD and high temperature in situ Raman spectroscopy techniques were carried out in order to elucidate the relation between the redox property of the Rh species in the Rh/Al2O3 with different Rh loadings and the performance of the catalysts for the reaction. Three kinds of oxidized rhodium species, i.e. the rhodium oxide species insignificantly affected by the support (RhOx), that intimately interacting with the Al2O3 surface (RhiOx) and the Rh(AlO2)y species formed by diffusion of rhodium oxides in to sublayers of Al2O3 [C.P. Hwang, C.T. Yeh, Q.M. Zhu, Catal. Today, 51 (1999) 93.], were identified by H2-TPR and O2-TPD experiments. Among them, the first two species can be easily reduced by H2 at temperature below 350 °C, while the last one can only be reduced by H2 at temperature above 500 °C. The ignition temperatures of POM reaction over the catalysts are closely related to the temperature at which most of the RhOx and RhiOx species can be reduced by CH4 in the reaction mixture. Compared to the Rh/Al2O3 with high Rh loadings, the catalysts with low Rh loadings contain more RhiOx species which possess stronger RhO bond strength and are more difficult to be reduced than RhOx by the reaction mixture. Higher temperature is therefore required to ignite the POM reaction over the catalysts with lower Rh loadings. The oscillation during the POM reaction over the Rh/Al2O3 with low Rh loadings can be related to the behaviour of Rh(AlO2)y species in the catalyst switching cyclically from the oxidized state to the reduced state during the reaction. 相似文献
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采用液相沉淀法制备Co3O4氧化物,并以其为载体制备负载型Rh催化剂。考察不同焙烧温度制备的载体和催化剂的结构、织构、氧化还原性能及其对C3H6催化还原NO性能的影响。结果发现,经600℃焙烧的载体制备的Rh/Co3O4催化剂中Rh与Co3O4的相互作用较强,促进对N—O键的削弱作用,提高对C3H6还原NO的还原能力。在相同实验条件下,当体系中C3H6为500×10-6、NO为500×10-6和O2体积分数为5%时,NO转化率50%,催化性能优于Rh/Al2O3催化剂。 相似文献