Periodic operation studies on the partial oxidation of propylene to acrolein and acrylic acid

Abstract Can periodic operation improve the selectivity in partial oxidation? Experiments were performed using a proprietary Sb/Sn/V oxide catalyst with a differential microcatalytic reactor free of transport limitations. Most experiments were performed at atmospheric pressure and 340°C. Steady-state experiments showed a strong effect of water on selectivity as well as rate inhibition by propylene. Thus, two strategies were explored: water cycling and propylene cycling. Compared with the highest values attainable under steady state, water cycling resulted in only a small selectivity improvement and time-average rates of formation were always lower. Large improvements occured with propylene cycling: as high as 90% for the rate of formation of acrylic acid and 40% for acrolein.