Production of bioethanol by direct bioconversion of oil-palm industrial effluent in a stirred-tank bioreactor
- 336 Downloads
The purpose of this study was to evaluate the feasibility of producing bioethanol from palm-oil mill effluent generated by the oil-palm industries through direct bioconversion process. The bioethanol production was carried out through the treatment of compatible mixed cultures such as Thrichoderma harzianum, Phanerochaete chrysosporium, Mucor hiemalis, and yeast, Saccharomyces cerevisiae. Simultaneous inoculation of T. harzianum and S. cerevisiae was found to be the mixed culture that yielded the highest ethanol production (4% v/v or 31.6 g/l). Statistical optimization was carried out to determine the operating conditions of the stirred-tank bioreactor for maximum bioethanol production by a two-level fractional factorial design with a single central point. The factors involved were oxygen saturation level (pO2%), temperature, and pH. A polynomial regression model was developed using the experimental data including the linear, quadratic, and interaction effects. Statistical analysis showed that the maximum ethanol production of 4.6% (v/v) or 36.3 g/l was achieved at a temperature of 32°C, pH of 6, and pO2 of 30%. The results of the model validation test under the developed optimum process conditions indicated that the maximum production was increased from 4.6% (v/v) to 6.5% (v/v) or 51.3 g/l with 89.1% chemical-oxygen-demand removal.
KeywordsPalm-oil mill effluent (POME) Bioethanol Direct bioconversion T. harzianum S. cerevisiae
The authors are grateful to the Research Management Centre, IIUM, for approving a Research Grant IIUM Fundamental Research Grant (IFRG) as well as to the Department of Biotechnology Engineering for providing the lab facilities.
- 4.Hassan MA, Yacob S, Shirai Y, Hung Y-T (2004) Treatment of palm oil wastewaters. In: Wang LK, Hung Y, Lo HH, Yapijakis C (eds) Handbook of industrial and hazardous wastes treatment. Marcel Dekker, New York, pp 719–736Google Scholar
- 7.Cheong WC, Hassan MA, Abdul Aziz S, Abdul Karim MI, Sabaratnam V, Shirai Y (2004) Treatment of palm oil mill effluent (POME) coupled with biohydrogen production. In: Proceedings of the Asia Water Conference, 1–2 April 2004, Kuala Lumpur, MalaysiaGoogle Scholar
- 8.Alam MZ, Muyibi SA, Mansor MF, Wahid R (2006) Removal of phenol by activated carbons prepared from palm oil mill effluent sludge. J Environ Sci (China) 18:446–452Google Scholar
- 9.Muniandy R (2000) Stone mastic asphalt with oil palm fibre for Malaysian road. In: Ariffin K, Hussein MA, Jainudeen MR, Singh N (eds) Inventions, innovative research and products. University Putra Malaysia, Kuala Lumpur, p 27Google Scholar
- 21.Mansor MF (2008) Process optimization on production of lignin peroxidase of sewage treatment plant sludge in a stirred tank bioreactor and its biodegradation of synthetic industrial dyes. Master’s Thesis, Faculty of Science, International Islamic University MalaysiaGoogle Scholar
- 24.Alam MZ, Kabbashi NA, Mamun AA, Tompang MF (2007) Development of single-step bioconversion for bioethanol production by fungi and yeast using oil palm fruit bunches. Malays J Chem Eng 1:29–39Google Scholar
- 25.Zain KHM (2006) Direct production of bioethanol by liquid state bioconversion of palm oil mill effluent (POME). BSc Thesis, Faculty of Engineering, International Islamic University MalaysiaGoogle Scholar
- 26.HACH (2002) Analysis handbook, 4th edn. HACH, Loveland, CO, p 185, 355, 383, 749Google Scholar
- 27.APHA (1989) Standard methods for the examination of water and wastewater, 17th edn. American Public Health Association, Washington DCGoogle Scholar
- 34.Kosaric N (1996) Ethanol-potential source of energy and chemical products. In: Rhem HJ, Reed G (eds) Biotechnology, 2nd ed, vol 6. Wiley-VHC, New York, pp 169–172Google Scholar
- 35.Rizzi M, Klein C, Schulze C, Bui-Thanh NA, Dellweg I (1989) Xylose fermentation by yeast 5: use of ATP balances for modeling oxygen-limited growth and fermentation of yeast Pichia stipitis with xylose as carbon source. Biotechnol Bioeng 34:509–514. doi: 10.1002/bit.260340411 PubMedCrossRefGoogle Scholar