Enzymatic Synthesis of Biodiesel Using Immobilized Lipase on a Non-commercial Support

In this work was produced an immobilized biocatalyst from Cercospora kikuchii lipase with beneficial catalytic activity and stability. The immobilized derivative was used in the ethanolysis of coconut oil. This is a great option for the Brazilian renewable fuel production, because both coconut oil and ethanol are promptly available in the country, at a reasonably low cost. For this, lipase was immobilized on rice husk (5.5 mg(protein) g(support)(-1)) by covalent binding using spouted bed drying (gas flow rate, 0.66 m(3) min(-1); temperature, 100 degrees C; and solution flow rate, 5.5 g min(-1)). In a typical batch run, the immobilized derivative was added at a vegetable oil/ethanol molar ratio of 1:12 using tert-butanol as the solvent. The feasibility of immobilization and drying processes was demonstrated toward biodiesel production, attaining a high ester content (97.1%) and low levels of acylglycerides (0.9%) after 72 h. Further properties, such as viscosity (4.56 mm cm(-2)) and density (888 kg m(-3)), are in agreement with specifications required by the ASTM D6751 to be used as alternative biofuel.