Direct partial oxidation of benzene to phenol on zeolite catalysts

Abstract

The partial oxidation of benzene to phenol at 330°C over various silica/alumina zeolite catalysts, using nitrous oxide as the oxidising agent, has been studied. An initial phenol yield of around 28% (based on benzene converted) was obtained over the protic form of ZSM-5 type zeolites, although this decreased to about 16% over a period of 24 h: no phenol at all was detected over Na-ZSM-5. An amorphous silica/alumina, and EU-1 type zeolites were also tested and were found to be much less active than the H-ZSM-5 materials. It is concluded that a zeolite possessing both Brønsted acidity and a particular internal structure is required to produce active and selective catalysts.