One-step selective oxidation over a Pd-based catalytic membrane; evaluation of the oxidation of benzene to phenol as a model reaction

The concept of a Pd-based catalytic membrane reactor (CMR) for the one-pot formation of phenol from benzene oxygen and hydrogen via "in situ" generated H2O2 was studied as a model reaction. Both technical and economic feasibility studies were performed to validate this concept. Results from the literature were confirmed but additionally we observed the total oxidation of benzene. Under the process conditions used, side-reactions such as total oxidation of hydrogen and benzene to water and CO2 are favoured. This accounts for the observed low yield of phenol. Consequently, this interesting CMR concept is still far from commercial application. (C) 2004 Elsevier B.V. All rights reserved.