A combined DFT and kMC study of reaction kinetics for the acetoxylation of propylene to allyl acetate on PdCu catalysts

Abstract

Allyl acetate is a vital intermediate in organic synthesis, which is produced by the acetoxylation of propylene on PdCu catalysts and mainly used for the synthesis of allyl alcohol and a range of derivatives, including 1,4-butanediol. Nevertheless, the absence of reaction kinetics in this process imposes limitations on the reactor design and process optimization. By combining Density Functional Theory and kinetic Monte Carlo simulations, the reaction kinetics were systematically studied. The critical oxygen concentration of the reaction system was calculated, and the feed molar ratio of oxygen was determined to be 8 %. The feed molar ratio of acetic acid was set to be 16 % to keep higher turnover frequency of allyl acetate and lower energy consumption. The preferential formation route of allyl acetate was obtained and the turnover frequency and space-time yield of allyl acetate were calculated. The apparent activation energy was determined to be 62.35 kJ⋅mol^-1. Finally, the reaction kinetic equation was derived and the kinetic parameters were obtained by fitting the data of space-time yield. This work provides theoretical guidance for reactor design and technological process improvement on microscopic and mesoscopic scales. Of particular significance is the contribution of a novel approach to the acquisition of reaction kinetic equations, which has a good application prospect.