Kinetics of enzymatic transesterification and thermal deactivation using immobilized Burkholderia lipase as catalyst

The most effective way of enzymatic synthesis of biodiesel is through lipase-catalyzed transesterification, while its performance and economic feasibility should still be improved. In this study, lipase produced by an isolated Burkholderia sp. was immobilized on microsize Celite materials functionally modified with long alkyl groups. The specific activity of the immobilized lipase was 1,154 U/g. The methanolysis of olive oil catalyzed by the immobilized lipase obeyed Ping Pong Bi Bi model with an estimated V _max, K_m,TG, K_m,M and K_i,M value of 0.61 mol/(L min), 7.93 mol/L, 1.01 mol/L, and 0.24 mol/L, respectively. The activation energy of the enzymatic reaction is estimated as 15.51 kJ/mol. The immobilized lipase exhibits high thermal stability with thermal deactivation energy of 83 kJ/mol and a long half-life. The enthalpy, Gibb's free energy, and entropy of the immobilized lipase were in the range of 80.02-80.35 kJ/mol, 88.35-90.13 kJ/mol, and -28.22 to -25.11 J/(mol K), respectively.