Date of Award

Fall 2012

Project Type


Program or Major

Chemical Engineering

Degree Name

Master of Science

First Advisor

Palligarnai T Vasudevan


In this thesis, the effect of organic solvent-cosolvent system, temperature, methanol concentration, water content and used enzyme washing method on transesterification of waste vegetable oil catalyzed by Thermomyces lanuginosus lipase immobilized on zeolite ZSM-5 was investigated. Four organic solvents, one co-solvent, three reaction temperatures, three methanol addition methods, four different water content and two used-enzyme washing methods were assessed. Optimal conditions were obtained with n-hexane as solvent, 5 vol.% tert-butanol as co-solvent, 25°C reaction temperature, batch addition of 3 equivalent molar methanol, water content equivalent to 7.5% by weight, and used-enzyme washing method B. It was also confirmed that the transesterification reaction catalyzed by used Thermomyces lanuginosus lipase immobilized on zeolite ZSM-5 was limited by the concentration of acyl acceptor, and that active water loss was related to enzyme activity lost after every reaction cycle.