Hydrocarbon Synthesis through CO2 Hydrogenation over CuZnOZrO2/zeolite Hybrid Catalysts

Abstract

Direct syntheses of hydrocarbons from CO2 hydrogenation were investigated over hybrid catalysts consisting of methanol synthesis catalyst (CuZnOZrO2) and zeolites (MFI and SAPO). The yield of hydrocarbons was strongly depending upon the amount of zeolite's acid sites as measured by NH3 TPD, while the product distributions were hardly affected by the change of acidity. The main product was ethane in the case of MFI hybrid catalyst and C-3 or C-4 hydrocarbon in the case of SAPO hybrid catalyst. This difference in product distribution was attributed to different mechanism of hydrocarbon formation. Investigation based on the ethene co-reaction suggested that the consecutive mechanism operated for HZSM-5 and the carbon pool mechanism for SAPO. (C) 1998 Elsevier Science B.V. All rights reserved.