Kinetic study of lipase-catalyzed esterification of furoic acid to methyl-2-furoate

Methyl-2-furoate (MF) is a high-value compound, and can be produced via esterification of furoic acid derived from biobased furfural. Herein, CAL-B and [bmim][PF 6 ] were the most efficient lipase and organic medium for MF production, respectively. Based on mass action law and reaction reversibility, a mathematical model was developed. Data analysis showed the newly proposed binary regression was apparently more suitable compared to the commonly used unitary regression. The enzymatic promotion factor m i for esterification and hydrolysis was 1.8159 and 0, while the alcohol inhibition factor n i was 0 and 0.06436, respectively. Both the activation energy E a, i for esterification and hydrolysis was 84 kJ/mol, and the pre-exponential factor A i was 7.1408×10 13 and 7.8962×10 13 , respectively. Kinetics study demonstrated that CAL-B held significantly more dominant esterification activity compared to hydrolysis activity, whereas alcohol just inhibited hydrolysis activity instead of esterification activity, and the relationship between esterification/hydrolysis rate constants k i and temperature agreed with Arrhenius equation. The maximum MF yield was 82.5 % at 24 h, and the yield decreased to 75.4 % after 1 re-use of CAL-B, but maintained about 20 % for next 4 cycles. Totally, the developed model and binary regression analysis method is ideal for in-depth examination of lipase-catalyzed kinetics in heterogeneous system.