Preparation and properties of lipase immobilized on MCM-36 support

Based on pure MCM-22 precursor, MCM-36 was produced by swelling and pillaring with SiO2 pillars. These materials were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), thermogravimetric analysis/differential scanning calorimetry (TGA/DSC), MAS NMR, and N2 adsorption isotherms. Compared with the MCM-22 sample, the resulting MCM-36 material contains a mesoporous region between the microporous layers, with a mesopore volume of 0.472 cm3/g, and the surface area increased up to 671 m2/g. Lipase from Candida antarctica B (CALB) was immobilized on both supports by physical adsorption at equilibrium. Twenty milligrams of CALB/g of MCM-22 was adsorbed on the external surface of crystals, while only 4 mg CALB/g support was adsorbed onto the mesoporous hybrid material MCM-36. The mechanism of adsorption was also discussed. The acylation of alcohols (1-butanol and 1-octanol) by vinyl esters (vinyl acetate and vinyl stearate) was used as a test reaction in order to evaluate the catalytic activity of MCM-36-immobilized lipase. The test reaction indicated MCM-36-immobilized enzyme as an active catalyst for the acylation and its activity was approximately two times higher than that of the free lipase (for the vinyl acetate/1-butanol system).