On the structure-sensitivity of 2-butanol dehydrogenation over Cu/SiO2 cogelled xerogel catalysts

Cu/SiO2 cogelled xerogel catalysts were synthesized by cogelation of tetraethoxysilane (TEOS) and chelates of Cu with 3-(2-aminoethylamino)-propyltrimethoxysilane (EDAS). The resulting catalysts are composed of metallic crystallites with a diameter of about 3 nm located inside microporous silica particles and larger metallic particles with a diameter of 8–30 nm located outside silica network. Cu/SiO2 catalysts were tested for 2-butanol dehydrogenation. This reaction over Cu/SiO2 cogelled xerogel catalysts is a structure-sensitive reaction: large metallic particles located outside silica particles are responsible for the dehydrogenation reaction, while small metallic particles located inside silica particles do not participate to the reaction.