Nanoparticle cages as microreactors for producing acrolein from glycerol in the liquid phase

Abstract

Liquid phase dehydration of glycerol to acrolein commonly suffers from a low acrolein yield because of severe side reactions of chemically active acrolein with itself or glycerol in the reaction system. Rapid separation of acrolein from the reaction system is one of the effective strategies to increase the yield of acrolein. Herein, a renewable water-in-oil Pickering emulsion with silica nanoparticle cages as microreactors was designed for liquid phase glycerol dehydration to acrolein. The influences of the oil phase types on the droplet size of the Pickering emulsion and the yield of acrolein were investigated in a microreactor. The smaller Pickering emulsion droplet showed a superior ability to intensify the separation of chemically unstable acrolein molecules from the nanoparticle cages and thus improved the yield of acrolein. A droplet size of about 11 μm was obtained with peony seed oil as the oil phase, in which 84.6% of acrolein yield was achieved.