碳负载胶体金属铑催化气相甲醇羰基化反应

VAPOR PHASE CARBONYLATION OF METHANOL CATALYZED BY SUPPORTED COLLOIDAL RHODIUM CLUSTER CATALYSTS

碳负载胶体金属铑催化气相甲醇羰基化反应＊王茜刘汉范＊＊（中国科学院化学研究所，北京１０００８０）关键词负载胶体金属催化剂，胶体铑簇，活性炭，气相法，甲醇，羰基化，乙酸甲醇羰基化反应制备乙酸是一重要工业反应．６０年代末由Ｍｏｎｓａｎｔｏ公司开发的铑系均...

Two simple and mild processes were proposed for immobilizing the rhodium colloid on active carbon. Supported catalyst PVP Rh/C (PVP=poly (N vinyl 2 pyrrolidone)) is prepared by an one step method, in which rhodium (Ⅲ) ions were reduced by refluxed methanol in the presence of both PVP and active carbon, the rhodium particles dispersed in a nanoscopic scale from 2 nm to 7 nm on the surface of support. The particle size and size distribution of colloidal rhodium cluster on the support remain unchanged with diameter of 2￣4 nm when a two step procedure used, that is to prepare a PVP protected rhodium colloid first, and then immobilize the colloid onto the surface of active carbon by stirring with the support. These supported colloidal rhodium catalysts were tested for the vapor phase methanol carbonylation. The experimental results showed that the presence of PVP in the catalyst gave a beneficial effect on both activity and selectivity when conducting the reaction at 250℃.