Self supported macrocellular monolith, useful e.g. as photocatalyst for decontaminating gaseous pollutants, comprises material comprising titanium oxide matrix comprising titanium dioxide in anatase form or in rutile form

摘要

Self supported macrocellular monolith comprises a material comprising titanium oxide matrix comprising titanium dioxide in anatase form (at least 80 wt.%) or in rutile form (at most 20 wt.%), where the monolith is free of micropores and macropores having an average size of 100 nm to 3 mu m and mesopores interparticle having the average size of 2-20 nm, and the pores are interconnected. An independent claim is included for preparing the self supported macrocellular monolith by a sol-gel process, comprising (a) preparing an aqueous solution of a cationic surfactant in a concentration of 10-40 wt.%, where the pH of the aqueous solution is less than 1, by adding a strong acid, (b) adding acid solution of cationic surfactant, under stirring, of at least one titanium oxide precursor, (c) stirring the reaction mixture for a time sufficient to hydrolyze the titanium oxide precursor, (d) preparing an emulsion by adding into the reaction mixture, dropwise with stirring, at least one volatile oil, (e) adjusting the pH of the reaction medium of 1.5-3 by adding a sufficient quantity of a strong base, (f) condensing the titanium oxide precursor by heat treating the reaction medium at 40-60[deg] C to obtain a titanium oxide monolith and (g) drying and calcining the obtained titanium oxide monolith at below 500[deg] C.