Catalytic vapor oxidation of toluene to benzaldehyde

It was investigated for the title reaction over multi components molybdates catalysts that the effects of reaction conditions such as temperature, the ratio of air and toluene, liquid toluene space velocity. There was a optimum temperature for oxidation of toluene to benzaldehyde. The conversion and selectivity to benzaldehyde increased with the increasing ratio of air and toluene. While space velocity increased, the conversion decreased and selectivity increased. The catalytic activity of several catalysts such as Mo-Cr, Mo-Mn, Mo-Cu, Mo-Ni, Mo-Co, Mo-Fe, Mo-Bi and Mo-Fe-Si were measured. Mo-Co catalyst was recommended. In membrane catalytic reactor, a certain feeding mode(toluene feeding in shell and air feeding in tube) was in favour of the reaction.