Abstract:

Catalysts of titanosilicate zeolite(TS-1) supported on silica gel microsphere were prepared after direct crystallization and calcination of the microspheric silica gel soaked in the TS-1 synthetic solution, in order to produce catalysts with good catalytic and recycling properties. The catalysts were characterized by XRD, IR and SEM, and were used in the synthesis of phenol by a direct oxidation of benzene with the hydrogen peroxide as the oxidant. The result showed that TS-1 molecular sieve was loaded on the surface of silica gel very well. On the conditions with the crystallization temperature at 160 ℃, crystallization time of 72 h, calcination temperature of 550 ℃, and calcination time of 6 h, the catalysts prepared showed good catalytic properties. On the conditions of the initial material content of benzene 0.5 mol and hydrogen peroxide 0.1 mol, catalyst 8 g, the reaction temperature at 60 ℃, and the reaction time 3 h, the convertion of benzene was 10.32%, and the selectivity to phenol was 97.12%. After recycling for nine times, the convertion of benzene was 9.42%, and the selectivity to phenol was 93.14%.

Key words: silica gel microsphere, supported catalyst, titanosilicate zeolite TS-1, benzene, phenol