Mesoporous bimetallic PdCl2-CuCl2 catalysts for dimethyl carbonate synthesis by vapor phase oxidative carbonylation of methanol
Mesoporous bimetallic PdCl2-CuCl2 catalysts for dimethyl carbonate synthesis by vapor phase oxidative carbonylation of methanol
复制标题
介孔双金属 PdCl2-CuCl2 催化剂用于甲醇气相氧化羰基化合成碳酸二甲酯
DOI：
10.1016/s0926-860x(02)00494-5
复制
发表时间：
2003-02-20
影响因子：
5.5
通讯作者：
Fan, KN
中科院分区：
文献类型：
--
作者：
Yang, P;Cao, Y;Fan, KN
在常压流动反应体系中，以介孔HMS SiO2为载体，季铵盐（QAS）为助催化剂，Pd Cl 2-CuCl 2为催化剂，甲醇氧化羰基化合成碳酸二甲酯（DMC）。考察了不同QAS助剂、助剂掺杂量、Cu/Pd摩尔比以及反应条件对催化剂活性的影响。结果表明，四丁基溴化铵（TBAB）促进的PdCl 2-CuCl 2/HMS催化体系具有最佳的催化性能。采用BET、X射线粉末衍射（XRD）、X射线光电子能谱（XPS）和漫反射红外光谱（DRIFT）等手段对PdCl 2-CuCl 2-TBAB/HMS催化剂进行了表征。TBAB促进剂的基本作用是促进Pd（0）/Pd（II）和Cu（II）/Cu（I）氧化还原过程。大量的表面稳定的亚铜物种的形成上的DMHMS催化剂上的DMC合成的催化性能的显着增强可能占。(C)2002 Elsevier Science B.V保留所有权利。
Dimethyl carbonate (DMC) synthesis reaction by oxidative carbortylation of methanol has been studied in a flow reaction system at atmospheric pressure in the presence of quaternary ammonium salt (QAS)-promoted bimetallic PdCl2-CuCl2 catalyst system supported on mesoporous HMS silica. The effects of the various QAS promoters, the promoter doping level and the Cu/Pd mole ratio were investigated, as well as the reaction conditions on the catalytic reactivates. The results showed that the tetrabutylammonium bromide (TBAB) promoted PdCl2-CuCl2/HMS catalyst system has the best catalytic performance. The characterization of PdCl2-CuCl2-TBAB/HMS catalysts was performed by means of BET, X-ray powder diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and diffuse reflectance infrared Fourier transform (DRIFT) spectroscopy. The essential role of TBAB promoter is to facilitate the Pd(0)/Pd(II) and Cu(II)/Cu(I) redox processes. The formation of substantial amounts of surface stabilized cuprous species on the bimetallic HMS catalysts may account for the significant enhancement of the catalytic performance in DMC synthesis. (C) 2002 Elsevier Science B.V All rights reserved.