Comparison in Dimethyl Ether Steam Reforming of Conventional Cu-ZnO-Al2O3 and Supported Pt Metal Catalysts
Résumé
The catalytic performance of platinum based catalysts supported on CeO2/Al2O3 (with different proportion of both oxides) was compared to the conventional Cu-ZnO-Al2O3 (CZA) catalyst for methanol steam reforming (MeOH-SR), which is the second stage in the dimethyl ether steam reforming (SRD) process for obtaining H-2. The catalytic performances of Pt based catalysts were notably influenced by the addition of CeO2 to the support: a higher content of CeO2 improved the catalyst activity and selectivity to H-2, and limited to some extent CO and CH4 formation. At low temperatures (below 350 degrees C), the copper based CZA catalyst provided the best results in MeOH-SR, but at high temperature (350-500 degrees C) Pt/CeO2 and CZA showed similar catalytic performance. Consequently, Pt/CeO2 can be envisioned as a proper metallic function to be used in the bifunctional catalyst for SRD together with gamma-Al2O3 acid function, which requires temperatures above 350 degrees C for attaining high conversion in dimethyl ether hydrolysis.