Facile Utilization of Carbon Dioxide for the Esterification of Potassium Lactate to Butyl Lactate

The utilization of C아 is crucial for the sustainable growth of human society. Herein, we demonstrate the direct esterification of potassium lactate (KL) ,vith butanol and pressurized CO₂ to butyl lactate (BL). The pressurized C아 reacts with water to form carbonic acid, which promotes esterification. In a single batch reaction, 17% butyl lactate was obtained which was increased to 36% through two consecutive esterification cycles. Finally, the complete conversion of potassium lactate to butyl lactate was achieved using a very small amount of sulfuric acid (H₂SO₄). The proposed integrated process requires approximately 63% less mineral acid compared to the conventional lactate separation and purification processes. The effect of reaction parameters, mcluding reaction temperature, reaction time, CO₂ pressure and moisture content for the esterification of potassium lactate were explored.