Pickering emulsion stabilized by dual stabilizer: A novel reaction/separation system for methacrolein synthesis

Abstract

A reaction/separation system composed of water-in-oil Pickering emulsion was constructed for the synthesis of methacrolein. The catalyst (diethanolamine acetate) aqueous solution was encapsulated in numerous emulsion droplets which were stabilized by dual stabilizer system and could be recycled and separated from product by filtration. The dual stabilizer system consisted of methyl–modified silica nanoparticles and monoglyceride. The effect of stabilizer system and dispersed phase on the Pickering emulsion properties were investigated, such as stability, rheological property, interfacial property and droplet size. The effect of emulsion properties on the catalytic performance was also studied. The strong stability, large interface area and proper particle layers of Pickering emulsion stabilized by dual stabilizer determined its excellent reactivity and catalyst efficiency. The Pickering emulsion showed good reaction stability in 8 cycles and could be used to produce methacrolein continuously for at least 72 h by filling in a column reactor.