Reaction–Thin Film Evaporation Coupling Technology for Highly Efficient Synthesis of Higher Alkyl Methacrylate

Abstract

The traditional methacrylic esterification process, which couples reaction–distillation/rectification, suffers from issues such as prolonged reaction time, high risk of self-polymerization, and low utilization rate of methacrylic acid. By optimizing the esterification reaction of methacrylic acid through reaction–thin film evaporation coupling, compared to the reaction–distillation coupling process, the reaction time could be reduced by 37.50%, the reaction temperature could be lowered by over 15 °C, and the yield of etherification of dodecanol could be decreased by 81.25%, which significantly mitigates the risk of self-aggregation and reduces energy consumption. Furthermore, the feasibility of recovery of methacrylic acid from aqueous phase through extraction with higher aliphatic alcohol was verified, the recovery rate of methacrylic acid could reach above 96.95%, and the extracted phase could be directly utilized for preparing raw material for esterification reaction without requiring further separation steps, which effectively enhances the process economy and atomic utilization.