Acrylic Acid Synthesis from Lactide in a Continuous Liquid-Phase Process

Abstract

Synthesis of bulk chemicals from biogenic resources is gaining increasing interest in industry and academia. In the present study, we demonstrate the continuous production of acrylic acid (AA) from biogenic lactide in a liquid-phase reaction using the ionic liquid tetrabutylphosphonium bromide as reaction medium and 2-bromopropionic acid as acid catalyst precursor. We here present a first continuous setup for AA production from LA derivatives in the liquid phase on a 10 L scale. The process operates at 200 °C and leads to AA yields of 72% in industrially relevant space–time–yields of up to 50 g/(h·L). We demonstrate continuous operation over 6 h time-on-stream, efficient product isolation and successful catalyst recycling.