Epoxidation of propylene with H2 and O2 in the explosive regime in a packed-bed catalytic membrane reactor

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 packedbed reactor. At 180 degrees C, the C3H6 conversion was 10% and the PO selectivity was 80%, corresponding to a space-time yield of 150 g(PO) kg(-1) h(-1), whereas at 212 degrees C, the yield increased to 200 gpo kg(cat) (-1) h(-1)cat The kinetic dependency, rpo = k (H-2)(0.53) (O-2)(0.26) (C3H6)(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. (c) 2008 Elsevier Inc. All bights reserved.