Catalytically Active Composite Material Based on TiO2/Cr2O3 Hollow Spherical Particles

Resumo

A method for the preparation of a SiO₂–TiO₂/Cr₂O₃(840) porous composite material in a block form with walls made of a silicate matrix and the interconnected channels of the matrix containing TiO₂/Cr₂O₃(840) spherical hollow oxide composites was proposed. The specific surface area (S_sp) of the block composites was 212.2 m²/g, which is 20 times greater than the value of S_sp for spherical composites not fixed in the silicon(IV) oxide matrix. The composition of the TiO₂/Cr₂O₃(840) and SiO₂–TiO₂/Cr₂O₃(840) samples was studied by X-ray diffractometry and X-ray microanalysis, which indicated the presence of chromium(III) oxide, titanium(IV) oxide, and an amorphous silicon(IV) oxide phase in the latter. The SiO₂–TiO₂/Cr₂O₃(840) block composite material exhibited catalytic activity in the deep oxidation reaction of para-xylene: a 100% conversion of the organic substance was achieved at a temperature of 350°C.