V/sub 2/O/sub 5//TiO/sub 2/-SiO/sub 2/ and V/sub 2/O/sub 5/-WO/sub 3/-CuO/TiO/sub 2/-SiO/sub 2/ catalysts for De-NO/sub x/ were prepared, using a sol-gel method for preparing catalytic support(TiO/sub 2/-SiO/sub 2/) and a modified impregnation method for coating the active compounds on the supports. The specific surface area, total pore volume, pore size distribution, crystallinity and homogeneity of the particles obtained were studied using BET, XRD, SEM, TEM and EDS analyses. Using a modified impregnation method, the active compounds were well dispersed on TiO/sub 2/-SiO/sub 2/ supports. These catalysts have a high activity on De-NOx process and even in the existence of SO/sub 2-/. It is showed that, V/sub 2/O/sub 5/-WO/sub 3/-CuO/TiO/sub 2/-SiO/sub 2/ achieves a 100% conversion of NO in the existence of SO/sub 2/ at 623 K.
