Novel copper phosphates with high catalytic activities under mild conditions

Conventionally, heterogeneous catalysts are mainly focused on the materials with large surface area such as TS-1 (350 m(2 .) g(-1)), and the materials with relatively small surface area (< 10 m(2) (.) g(-1)) are generally ignored. This review summarized the catalytic activities and mechanism in a series of oxidations by H2O2 or oxygen as oxidants over novel copper phosphates with very small surface area less than 1.4 m(2) (.) g(-1). In the hydroxylation of phenol and benzene by H2O2, the high activities of this catalyst are comparable to those of TS-1. In epoxidation of styrene by H2O2, the selectivity for epoxide is much higher than that of TS-1. In hydroxylation of 2, 3, 6-trimethylphenol by H2O2, it showed good activity and high selectivity for trimethylhydroquinone. In oxidation of olefins and alcohols by O-2, the catalysts exhibited remarkable catalytic results. The characterization of ESR and IR spectroscopies shows that hydroxyl radicals and peroxide species are important intermediates in these oxidations.