Efficient CuZn/SiO2 lamellar catalysts for methanol dehydrogenation: New insights into the role of zinc

CuZn/SiO2 lamellar catalysts are obtained through the introduction of zinc oxide with different amount to Cu/SiO2 prepared by the ammonia-evaporation method and investigated for the dehydrogenation of methanol to methyl formate. The 20CuZn/SiO2 catalyst showed the best catalytic activity with a methanol conversion of 44.5% and a selectivity to methyl formate of ~92.7% at 300 °C and 0.2 MPa. The reason for this excellent activity could be ascribed to the strong interaction between Cu and ZnO, which promoted the decomposition of the copper phyllosilicate precursor to release copper oxide and thereby achieved more active Cu0 species upon reduction on the catalyst surface. In addition, the agglomeration of Cu species was mainly responsible for the slight decline in the methanol conversion in ZnO modified Cu based catalysts for the methanol dehydrogenation reaction.