Effect of calcination temperature on the catalytic activity of VPO for aldol condensation of acetic acid and formalin

•VPO catalysts were developed for one step synthesis acrylic acid with HAc and HCHO.•The influence of calcination temperature on VPO catalysts was studied.•Larger surface area and higher V4+/V5+ ratio favored higher yield of main product.•The catalyst deactivation was explored using XPS method. The effect of calcination temperature on the catalytic activity of VPO catalyst for one step synthesis acrylic acid with acetic acid and formalin was systematically studied using a fixed-bed tubular micro-reactor. The influence of calcination temperature on physicochemical properties especially crystal phase structure of VPO catalysts was obtained. The catalysts were analyzed and characterized with in situ high temperature XRD (HT-XRD), BET, TEM, TG/DTA, XPS, as well as NH3, CO2-TPD, and pyridine-FTIR methods. Larger special surface area and higher V4+ concentration favored higher conversion and selectivity. The optimum special surface area and IV4+/IV5+ ratio was obtained with controlling calcination temperature. The catalyst deactivation was also explored.