P51: Development of novel lipase supporter using activated carbon for biodiesel production

Carbon materials, especially activated carbon, exhibit much higher surface area than other conventional catalyst support and also it is relatively cheap. Then, activated carbon was employed as a supporter for enzyme. In this study, novel lipase immobilization system which utilizes activated carbon as a new supporter was developed. An improved method based on our previous immobilization process was suggested. The immobilization process has several steps which contain oxidation of activated carbon, modification of activated carbon oxide(ACO) surface by silanization, crosslinking by glutaraldehyde and coupling of lipases on the ACO supporter. After immobilization, SEM image analysis and FTIR analysis were conducted to confirm the change of ACO surface and formation of functions. In the results of SEM analysis, porous and rugged surfaces were observed visually, and FTIR results revealed the characteristic band of amide and carboxyl group at 3500-3700cm^-1 and 1650-1750 cm^-1, respectively. Novel enzyme immobilization method was investigated that two kinds of lipases were bound on ACO surface at a time. Also optimal amount of enzyme loading ratio for efficient immobilization process was investigated and after that, enzyme activity was measured. The optimal ratio of the process was found to be a 1:1 ratio of C. rugosa and R. oryzae lipases, and when the optimum was employed, immobilized lipases activity was measured to be approximately 5000 U/g matrix. Biodiesel production using lipases immobilized on ACO was performed at 45°C and 300 rpm for 4 h. The FAME contents were about 80.0% during 4 h of batch process.