Epoxidation of propylene with H 2 and O 2 in the explosive regime in a packed-bed catalytic membrane reactor

Abstract

The vapor-phase epoxidation of propylene with H 2 and O 2 over a highly dispersed Au/TS-1 catalyst was carried out in a packed-bed catalytic membrane reactor. The membrane reactor allowed the use of high concentrations of H 2 and O 2 (40% each) that were well within the explosive regime, and the production rate of propylene oxide was improved by 100–200% compared with that from a conventional packed-bed reactor. At 180 °C, the C 3H 6 conversion was 10% and the PO selectivity was 80%, corresponding to a space–time yield of 150 g PO kg cat −1 h −1 , whereas at 212 °C, the yield increased to 200 g PO kg cat −1 h −1 . The kinetic dependency, r PO = k (H 2) 0.53 (O 2) 0.26 (C 3H 6) 0.18, obtained free from mass transport and heat transfer limitations at these high concentrations was in good agreement with that reported at low concentrations.