助剂对球形Cu/SiO2催化剂甲醇脱氢制甲酸甲酯反应性能的影响OACSTPCD

Methanol dehydrogenation to methyl formate is a green and efficient way to diversify methanol downstream products.The modification of Cu/SiO2 catalyst with additive has become an effective strategy to increase the yield of the target product methyl formate.Firstly,spherical SiO2 supported Cu catalyst(Cu/SiO2)was prepared by the sol-gel method,and then a series of CuM/SiO2(M = Ce or Al)catalysts were obtained through the introduction of additive to Cu/SiO2 via the rotary evaporation method.The catalysts were characterized by N2 absorption/desorption,scanning electron microscopy(SEM),H2-N2O titration,X-ray diffraction(XRD)and so on,and their catalytic performances were evaluated for the reaction of methanol dehydrogenation to methyl formate.The results show that the additive can change the content of active Cu0 species and the surface acidity of the catalysts.Compared with the Cu/SiO2 catalyst,the dispersion of Cu particles on the surface of CuCe/SiO2 catalyst is increased,which promotes the formation of the active species Cu0,while the surface alkaline site is reduced,which inhibits the occurrence of side reactions,and thus exhibits the highest activity.Under the reaction conditions of 300 ℃ and 0.2 MPa,the methanol conversion rate and the selectivity of methyl formate of CuCe/SiO2 catalyst are 29.2％and 86.3％,respectively,and the yield of methyl formate is 25.2％,which are obviously better than that of Cu-based catalysts reported in the literature.