铯基固体碱催化剂用于醋酸甲酯与甲醛缩合制丙烯酸甲酯  

Cs-based solid catalyst for the synthesis of methyl acrylate by condensation of methyl acetate and formaldehyde

作　　者：余强 王海之 刘晓曦 Yu Qiang;Wang Haizhi;Liu Xiaoxi(SINOPEC Shanghai Research Institute of Petrochemical Technology,State Key Laboratory of Green Chemical Engineering and Industrial Catalysis,Shanghai 201208,China)

机构地区：[1]中石化(上海)石油化工研究院有限公司,绿色化工与工业催化全国重点实验室,上海201208

出　　处：《工业催化》2023年第6期38-44,共7页Industrial Catalysis

摘　　要：醋酸甲酯和甲醛缩合制备丙烯酸甲酯的新工艺路线引起了学术界和工业界的广泛关注。采用等体积浸渍法制备氧化硅负载铯固体碱催化剂并用于醋酸甲酯与甲醛缩合制丙烯酸甲酯反应。通过TG-MS、SEM、Raman、XRD、CO_(2)-TPD和反应性能评价等手段,重点考察不同铯基前驱体对催化剂结构和反应性能的影响。结果表明,碳酸铯和醋酸铯为前驱体制备得到的固体碱催化剂性能相近且性能最优,而硝酸铯前驱体制备的催化剂性能较低,可能是由于在406℃时硝酸铯出现熔融再结晶,导致活性相分散性变差。碳酸铯和醋酸铯前驱体制备的催化剂在高温焙烧条件下活性中心均以Cs 2CO_(3)相存在。进一步考察碳酸铯的负载量对性能的影响,以5%负载量时催化剂性能最优,醋酸甲酯转化率约20%,丙烯酸甲酯选择性约87%,催化剂稳定运行120 h,稳定性良好。The synthesis of methyl acrylate by condensation of methyl acetate and formaldehyde has attracted extensive attention in academia and industry.Herein,the Cs solid base catalysts supported by silicon dioxide were prepared by incipient-wetness impregnation method and employed.Combining the evaluation of catalyst performance with a series of catalyst characterization(SEM,Raman,XRD,TG-MS and CO_(2)-TPD),the effects of different Cs precursors on the structure and reaction performance of the catalysts were investigated.It was found that the catalyst prepared by cesium carbonate or cesium acetate precursor had superior performance,while that prepared by cesium nitrate precursor had lower performance,which may be due to poor dispersion of active phase caused by melting and recrystallization of cesium nitrate at 406℃.The active sites of the catalyst prepared by cesium carbonate or cesium acetate precursor exist in the form of Cs_(2)CO_(3) phase after high temperature calcination.The effect of cesium carbonate loading on the performance of the catalyst was further investigated.Under the optimal loading of mass fraction of 5%,conversion of methyl acetate is about 20% and selectivity of methyl acrylate is about 87%.The catalyst had been stable for 120 h,indicating excellent stability.

关 键 词：催化化学 固体碱催化剂 铯盐 缩合 丙烯酸甲酯 

分 类 号：TQ426.6[化学工程] O643.36[理学—物理化学]