Research on iron-molybdenum catalysts for methanol oxidation to formaldehyde

Iron-molybdenum catalysts with different Mo/Fe atom ratio for methanol oxidation for formaldehyde were prepared by co-precipitation method.Their catalytic performance were investigated in a conventional fixed bed reactor.The catalysts were characterized by BET,XRD and TEM.The results showed that the catalyst with Mo/Fe atom ratio of 2.2-2.8 and calcined at(400-450) ℃ possessed good catalytic activity and surface area,appropriate pore volume and pore size.Relatively stable MoO3 and Fe2(MoO4)3 crystal phase were formed,and the catalyst had higher activity and selectivity.Methanol conversion of 98% and formaldehyde yield of 93% were attained under the optimal reaction condition as follows:reaction temperature(265-315) ℃,space velocity(8 500-13 000) h-1.The results of 500 h life experiment showed that the catalyst exhibited high catalytic activity and stability.