Use of a whole-cell biocatalyst to produce biodiesel in a water-containing system

• Published in: Journal of environmental science and health. Part A, Toxic/hazardous substances & environmental engineering Vol. 44; no. 1; pp. 21 - 28
• Main Authors: Jin, Guang, Bierma, Thomas J., Hamaker, Christopher G., Mucha, Raymond, Schola, Valeria, Stewart, Jeb, Wade, Caroline
• Format: Journal Article
• Language: English
• Published: Philadelphia, PA Taylor & Francis Group 01-01-2009; Taylor & Francis
• Subjects: Alcohol; Applied sciences; Biocatalysis; biodiesel; Bioelectric Energy Sources; biofuels; Esterification; Exact sciences and technology; Fatty acids; Gasoline; Hot Temperature; lipase; Oil; Pollution; Q1; Q2; Rhizopus - metabolism; Rhizopus oryzae; Temperature; transesterification; waste oils; Water - chemistry; Whole-cell biocatalyst; Whole-cell biocatalyst; Edible species; Grease; transesterification; lipase; Immobilization; waste oils; Fatty acids; biodiesel
• ISSN: 1093-4529; 1532-4117
• DOI: 10.1080/10934520802515202

This study examined the use of a whole-cell biocatalyst to transesterify triglycerides, including high-Free Fatty Acid (FFA) waste greases, in a water-containing system. The whole-cell biocatalyst derived from Rhizopus oryzae (ATCC10260) was grown and reacted at room temperature without immobilization. The effectiveness of improving biodiesel yield through alteration of reaction temperature, additional alcohol, and additional transesterification reaction was also examined. Results showed that whole-cell biocatalyst was able to produce biodiesel with a yield of about 75% for virgin canola oil, 80% for waste vegetable oil and 55% for brown grease with a 72-hr transesterification reaction using no excess methanol. Elevating the reaction temperature to 35°C significantly diminished the yield. An additional dose of methanol with another 24 hours of reaction time or a second 72-hr reaction resulted in biodiesel yield approaching 90% and only 3% residual glycerides (mono-, di- and tri-glycerides). These results suggest that whole-cell biocatalysts are able to transesterify waste oils or greases that are high in FFA and contain water. Brown (trap) grease and similar degraded or complex greases may be good candidates for further whole-cell biocatalyst research.