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磺化硅胶是一种以化学键键合而成,性能稳定的固体酸催化剂。实验以磺化硅胶为催化剂,乙酸和正丙醇为原料合成了乙酸正丙酯。以单因素法分别考察了酸醇摩尔比、反应时间、催化剂用量以及催化剂的重复使用次数对酯化率的影响。最佳合成条件为:n(乙酸)∶n(正丙醇)=1∶1,回流时间为60 min,催化剂用量为反应物总质量的1.2%,反应的酯化率可达93.4%,催化剂重复使用10次后的酯化率仍达81.1%。研究结果表明:磺化硅胶对乙酸正丙酯的合成具有良好的催化活性。 相似文献
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乙酸异丙酯合成中固体酸催化作用的研究 总被引:3,自引:0,他引:3
研究了几种强酸性阳离子交换树脂、SO4^2-/TiO2、SO4^2-/Fe2O3、SO4^2-/ZrO2等固体酸对异丙醇与乙酸酯化反应的催化作用,研究表明负载了微量稀土元素后的大孔网络型树脂GD001有较好的催化性能,运行160h后仍具有很好的稳定性和寿命 相似文献
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强酸性阳离子交换树脂负载金属离子催化制备乙酸正丙酯 总被引:2,自引:0,他引:2
以冰乙酸和正丙醇为原料,用强酸性阳离子交换树脂负载金属离子作为催化剂催化制备乙酸正丙酯,以乙酸的转化率作为考察指标,考察了树脂种类,负载四种金属离子及负载条件对催化剂性能的影响。用制备的负载催化剂,考察了酸醇摩尔比、反应时间、催化剂用量等对反应的影响,以及催化剂的重复使用性能。实验表明,负载金属锆离子的催化性能最好,负载条件为锆盐浓度为1.0%,负载温度为50℃,负载时间为1 h为最佳。反应最佳条件为反应酸醇摩尔比1∶1,反应时间3 h,催化剂用量为乙酸质量的20%,沸腾状态反应,反应的转化率为68.79%。催化剂经10次重复使用后催化能力没有明显的下降,说明催化剂的使用寿命较长。 相似文献
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合成肉桂酸正丙酯的催化剂研究进展 总被引:1,自引:0,他引:1
综述硫酸铁铵,杂多酸,氯化铁,TiSiW_(12)O_(40)/Ti_2,阳离子大孔交换树脂,SnCl_4·5H_2O,聚氯乙烯三氯化铁等几种不同催化剂催化合成了肉桂酸正丙酯的实验结果。结果表明:大孔阳离子交换树脂、杂多酸HPA和SnCl_4·5H_2O对肉桂酸正丙酯的合成反应具有良好的催化活性,具有实际应用价值。 相似文献
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间歇反应精馏合成乙酸异丙酯 总被引:2,自引:0,他引:2
以乙酸和异丙醇为原料通过间歇式反应精馏合成乙酸异丙酯,正交实验给出最佳合成条件为:回流比3、反应时间1.5h、乙酸与异丙醇的物质的量比1∶1.5、催化剂用量为乙酸体积2%,乙酸异丙酯的最大收率为92.8%。 相似文献
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Rakesh Kumar Sanjay M Mahajani Hemant Nanavati Santosh B Noronha 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2006,81(7):1141-1150
Lactic acid, being virtually a non‐boiling compound, is difficult to separate from its aqueous solution by conventional methods such as distillation. It is necessary to convert it to the relatively volatile ester and the separation of the ester, followed by hydrolysis, is recommended as an appropriate method of recovery. In the present work, we explore and investigate a novel reactive distillation strategy to perform esterification, distillation and hydrolysis in a single unit. The experiments were performed in a batch reactive distillation set‐up and the results have been explained with the help of an appropriate model. An unsteady state mathematical model based on an equilibrium stage concept was developed for batch reactive distillation. A pseudo‐homogeneous model was used for the determination of reaction kinetics. The effect of operating parameters such as feed concentration, mole ratio, catalyst loading, boil‐up rate, etc. on the recovery of lactic acid was studied with the help of simulation and experimental results. The feasibility issue of reactive distillation has been discussed based on the results obtained. Copyright © 2006 Society of Chemical Industry 相似文献
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本文研究了阳离子交换树脂吸附Fe3 的制备及其在合成乙酸丙酯反应中的催化作用 ,结果发现其具有较高的催化能力 ,乙酸丙酯的产率可达 76 %以上。 相似文献
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Rakesh Kumar Hemant Nanavati Santosh B Noronha Sanjay M Mahajani 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2006,81(11):1767-1777
Separation and purification of lactic acid from the fermentation broth are difficult because of its non‐volatile nature and the presence of other organic acids. Esterification of lactic acid with methanol followed by hydrolysis of the separated methyl lactate is an effective technique for this purpose. A continuous process for recovery is proposed and various aspects are evaluated through simulation and experiments. In the proposed route, a vapor stream containing methyl lactate is removed from a two‐phase CSTR, used for esterification, operated under boiling conditions. The ester thus separated from the aqueous solution is further hydrolyzed in a reactive distillation column. Continuous removal of the volatile component (i.e. methanol) from the reaction zone increases conversion, thus pure lactic acid is obtained from the bottom of reactive distillation column. The results obtained in the experiments are compared with the simulation results. Further simulation studies were performed to obtain the suitable operating conditions for higher conversion and concentration of lactic acid. Copyright © 2006 Society of Chemical Industry 相似文献