Preparation and Catalytic Properties of Chromia Supported Silica Pillared Zirconium Phosphate

Chromia supported silica piiiared zirconium phosphate was prepared by a novel way. In this method 3-aminopropyitriethoxysiian(APS) pillared zirconium phosphate was prepared first, after impregnation with Cr(NO₃)₃·6H₂O solution, the samples were calcinated at 550°C to transform it to chromia supported silica pillared zirconium phosphate.

Compared with the catalyst obtained by normal impregnation, the sample has stronger interaction between Cr and supporter which promoted the dispersion of chromia on supporter. There is not crystalline chromia when the content of chromia in samples is 50% and its specific surface area is up to 230 m²/g. In hydroxylation of benzene, the highest conversion of benzene is 29.6%, which is much higher than those samples prepared by normal way. In the same time, Cr leaching from samples decreased with the increase of Cr loading in the reaction, which indicates that the samples has a higher stability against the Cr leaching.