制备条件对CoLa/Al2O3催化剂上乙醇脱氢氨化制乙腈反应性能的影响OA北大核心CSTPCD

Ethanol dehydroamination is a clean,safe and economical way to obtain high purity acetonitrile.The effects of preparation conditions(calcination atmospheres and Co loadings)on the catalytic performances in ethanol dehydroamination to acetonitrile over xCo0.25La/Al2O3-y(x and 0.25 represent the loading(mass fraction,%)of Co and La,respectively,and y represents calcination atmospheres)were investigated in a fixed flow bed.And the reactions were carried out for 45 min at 410℃0.1 MPa,anhydrous ethanol space velocity of 0.5 h-1,and the ratio of ammonia to alcohol of 6:1.The catalysts were characterized by XRD,XRF,N2 absorption/desorption and CO pulse chemisorption.The results show that the metal active surface area of xCo0.25La/Al2O3-10H2/N2 first increases and then decreases with the increase of Co loading,and the reduced Co surface area of 10Co0.25La/Al2O3-10H2/N2 is 23.38 m2/g,and its acetonitrile selectivity is the highest(88.47%).10Co0.25La/Al2O3-10H2/N2 is continuously operated at 430℃for 120 h while other reaction conditions unchanged,and the acetonitrile selectivity rapidly decreases from the initial 88.32%to 66.80%at 21 h,and then satabilizes at about 65%.The corresponding selectivity of ethylamine and butyronitrile remain about 12%and 5%,respectively.