Novel and highly efficient lipase-catalyzed esterification of formic acid with hexanol for waste gas reutilization

Abstract The bioconversion of waste C1 gases into formic acid and hexanol is highly important for the sustainable synthesis of diverse chemicals from non-petrochemical sources and the reduction of greenhouse gas emissions. Herein, we valorized formic acid and hexanol by subjecting them to lipase-catalyzed esterification to afford hexyl formate. The maximum conversion was 98.28% with Novozym 435 of 15 g/L, a formic acid to hexanol molar ratio of 1:5, a reaction temperature of 40 °C, and with 1,2-dichloroethane as a solvent for 1.5 h. The original enzymatic activity was retained even after 20 cycles, while conversion was maintained above 95%. These results may generally contribute to the lipase-catalyzed synthesis of formate esters and be used to efficiently valorize waste C1 gases into short-chain flavored esters.