共沉淀法制备Ag-ZrO2-SiO2催化剂及其乙醇制丁二烯性能研究OA

Developing novel ethanol-to-butadiene catalysts is essential for enabling alternatives to the traditional butadiene production route.A series of Ag-ZrO2-SiO2 catalysts were prepared using co-precipitation method,in which the Zr precursor concentration was controlled.The catalysts were characterized by XRD,SEM,N2 adsorption/desorption,ICP-OES and Py-IR.Their catalytic performances in ethanol-to-butadiene were evaluated in a fixed-bed reactor to investigate the influence of acidity regulation on catalytic performance.The results show that controlling the Zr precursor concentration optimizes both the amount and strength distribution of Lewis acid sites,which promotes the main C-C coupling reaction of acetaldehyde while suppressing the side reaction of ethanol dehydration to ethylene.Under reaction conditions of 420℃ and weight hourly space velocity of 0.3 h-1,the AZS-2 catalyst(prepared by ZrO(NO3)2 solution with mass fraction of 10％)exhibits the best catalytic performance,achieving an ethanol conversion rate of 80.0％and a butadiene selectivity of 47.3％.Its ethylene selectivity is notably lower than that of other catalysts.