Low temperature aqueous phase oxidation of alkanes with metal doped zeolites prepared by chemical vapour infiltration

摘要

The low temperature oxidation of methane, ethane and propane to useful oxygenates in the aqueous phase using neat hydrogen peroxide is explored. High catalytic activity of metal doped zeolite catalysts in the target transformation of C1-C3 alkanes to their corresponding alcohols, aldehydes and carboxylic acids with low selectivity to carbon oxides (overoxidation products) has been achieved. Chemical vapour infiltration has been employed as the technique of choice to prepare metal doped zeolites used in this work with new methods to tune both selectivity to oxygenates and catalytic activity of these materials for alkane oxidation being presented. These new materials represent a step change in the design and application of zeolite catalysts for lower alkane oxidation from both a materials and oxidative chemistry perspective. The preparation technique has wider applicability in catalyst preparation and reproducibly affords very well dispersed and minute nanoparticles on a variety of support materials by an easily accessible methodology. Finally a new and innovative technique of catalyst preparation, with beneficial effects in alkane oxidation, dubbed “The Hybrid Method” is presented.