研究了一种可用于脂肪酸甲酯环氧化的类水滑石催化剂.采用共沉淀法合成类水滑石[Mg1-xAlx（OH）2]x＋-（NO3-）x mH2O,通过离子交换法制备出一种新的柱撑水滑石2 31 2[Mg-＋x A l x＋（O H）]x＋312 40/3[PW O]x-mH2O化合物,并由XRD,FT-IR,Raman,ICP和UV-Vis进行了表征.用制备的类水滑石应用于无羧酸环境下的催化脂肪酸甲酯环氧化反应,结果表明,柱撑水滑石较插层前转化率和选择性都有了明显的提高.考察了反应温度、反应时间、催化剂重复使用等因素对环氧化反应的影响,在60℃时反应16 h,转化率和选择性分别达到56.1%和59.4%,催化剂使用4次后重复使用率仍高于90%.对催化剂催化环氧化的机理进行了初步的探讨.%A kind of effective hydrotalcite-like catalysts which can be used in the epoxidation of fatty acid methyl esters were exploited in this work. The hydrotalcite-like compounds were synthesized by using the coprecipitation method, and then a novel pillared-hydrotalcite was obtained through ion-exchange method. Then, the catalyst activity was tested by epoxidation of fatty acid methyl esters without carboxylic acid, and the results indicate that pillared-hydrotalcite shows better catalytic performance. The effects of reaction time, temperature and catalyst reusability on the epoxidation of fatty acid methyl esters were discussed in detail. The conversion and selectivity of epoxy products reach 56.1% and 59.4% respectively at 60 ℃ for 16 h. After recycling 4 times, the recycle utility rate was still over 90%. Finally, the mechanism of interaction between the catalyst and oxidant was investigated.
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