Hydrophobic poly(ionic liquid)s as “two-handed weapons”: Maximizing lipase catalytic efficiency in transesterification of soybean oil toward biodiesel

The mesoporous supports of alkylated poly(ionic liquid)s (PILs) are got through free radical copolymerization . With an immobilization yield of 99% for Candida antarctica lipase B (CalB), the biocatalyst showed high advantage for biodiesel production under mild conditions. Typical catalyst CalB 0.2 @PIL-C8 was capable of effectively converting soybean oil into biodiesel with a yield of 68.2%, which is higher than Novozym 435 for 57.5%. The biodiesel yield was almost 1.5 folds compared to that of free CalB under the same conditions. And the catalyst remained about 80% activity in a seven-run recovery test with no CalB leaching in the whole process. The hydrophobic PILs not only provide a suitable reaction micro-environment but also can help CalB keep an open conformation in immobilizing with its flexible hydrophobic alkyl chains. This research offered a green and effective strategy for regulating the hydrophobicity and surface potential of support to enhance the performance of immobilized lipase.