American Journal of Energy Engineering
Volume 2, Issue 6, November 2014, Pages: 127-132
Received: Nov. 29, 2014;
Accepted: Dec. 17, 2014;
Published: Dec. 22, 2014
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Temesgen Atnafu Yemata, Institute of technology, Department of Chemical Engineering, Addis Ababa, Ethiopia; Addis Ababa University, Chemical Engineering Department, Addis Ababa, Ethiopia
Lignocellulosic materials (eg.Prosopis juliflora) can be utilized to produce ethanol, a promising alternative energy source for the limited crude oil. This study involved optimization of acid hydrolysis in ethanol production from prosopis juliflora. The conversion of prosopis juliflora to ethanol can be achieved mainly by three process steps: pretreatment of prosopis juliflora wood to remove lignin and hemicellulose, acid hydrolysis of pretreated prosopis juliflora to convert cellulose into reducing sugar (glucose) and fermentation of the sugars to ethanol using Saccharomyces cerevisiae in anaerobic condition. A two level full factorial design with four factors, two levels and two replicas (24*2=32 experimental runs) was applied to optimize acid hydrolysis and study the interaction effects of acid hydrolysis factors, namely, acid concentration, solid fraction, temperature, and time. An optimization was carried out to optimize acid hydrolysis process variables so as to determine the best acid concentration, solid fraction, temperature, and contact time that resulted maximum ethanol yield. The screening of significant acid hydrolysis factors were done by using the two-level full factorial design using design expert® 7 software. The statistical analysis showed that the ethanol yield of (40.91% (g/g)) was obtained at optimised acid hydrolysis variables of 0.5%v/v acid concentration, 5%w/w solid fraction, 105.01°C temperature, and 10 minutes hydrolysis time.
Temesgen Atnafu Yemata,
Optimisation of Acid Hydrolysis in Ethanol Production from Prosopis Juliflora, American Journal of Energy Engineering.
Vol. 2, No. 6,
2014, pp. 127-132.
B.Du et al., Bioconversion of forest products industry waste cellulosic to fuel ethanol: A review, Bioresource Technology.
Divya Paruchuri (December, 2008). Conversion of Hardwoods to Ethanol: Georgia.
Du et al., 2010, Comparative growth, biomass production, nutrient use and soil amelioration by nitrogenfixing.
Lin, Y., and Tanaka, S., 2006, Ethanol fermentation from biomass resources: current state and prospects, Applied Microbiology and Biotechnology 69: 627-642.
Mosier, N., et al., 2005, Features of promising technologies for pretreatment of lignocellulosic biomass, Bioresource Technology 96: 673-686.
Saha, B.C. and Bothast, R.J., (1997) Enzymes in lignocellulosic biomass conversion. ACS Symp.Ser. 666 46-56.
Senayit, R., Agajie, T., Taye, T., Adefires, W. and Getu, E (2004), Invasive Alien Plant control and Prevention in Ethiopia, Pilot Surveys and Control Baseline Conditions. Report submitted to EARO, Ethiopia and CABI under the PDF-B phase of the UNEP/GEF Project, removing Barriers to Invasive Plant Management in Africa. EARO, Addis Ababa.
Shiferaw, H., Teketay, D., Nemomissa, S. and Assefa, F. (2004). Some biological characteristics that foster the invasion of Prosopis juliflora (Sw.) DC at Middle Awash Rift Valley Area,Northeastern Ethiopia. Journal of Arid Environments 58/135.154.
Taherzadeh MJ, Eklund R, Gustafsson L, Niklasson C, Lide´n G. 1997. Characterization and fermentation of dilute-acid hydrolyzates from wood. Ind Eng Chem Res 36:4659–4665.
Taye, T., Ameha, T., Adefiris, W. and Getu, E. (2004). Biological Impact Asssessment on selected IAS Plants on Native Species Biodiversity, Report submitted to EARO, Ethiopia, tree species in semi-arid Senegal. Forest Ecology and Management 176: 253-264.
US Congress, 1984, Commercial Biotechnology: An International Analysis, report OTA-BA-218, US Congress, Office of Technology Assessment, Washington DC USA.
USDOE, 2003, Advanced bioethanol technology - website: www.ott.doe.gov/biofuels/, US Department of Energy, Office of Energy Efficiency and Renewable Energy, Office of Transportation Technologies, Washington DC USA.
Wyman, C.E., Dale, B.E., Elander, R.T., Holtzapple, M., Ladisch, M.R. and Lee, Y.Y., (2005) Coordinated development of leading biomass pretreatment technologies. Bioresour. Technol. 96 1959-1966).
Wheals AE, Basso LC, Alves DMG, Amorim HV. Fuel ethanol after 25 years. Trends Biotechnol 1999;17:482–7.
Wooley R, Ruth M, Sheehan J, Ibsen K, Majdeski H and Galvez A, 1999, Lignocellulosic biomass to ethanol - Process design and economics utilizing co-current dilute acid prehydrolysis and enzymatic hyrolysis - Current and futuristic scenarios, National Reneawable Energy Laboratory, Golden Colorade,USA.
Van Zyl, W., and Kargi, F., 2007, Consolidated Bioprocessing for bioethanol production using Saccharomyces cerevisiae Pages 205-235, Biofuels.
Vaccarino, C., Locurto, R., Tripodo, M. M., Patane, R., Lagana, G. and Ragno, A.(1989), "SCP from orange peel by fermentation with fungi–acid-treated peel," Biol. Wastes 30, 1-10.
Zhu JY, Pan XJ, Wang GS, Gleisner R (2009), "Sulfite pretreatment (SPORL) for Robust enzymatic saccharification of spruce and red pine". Bioresource Technology 100 (8): 2411–2418.doi:10.1016/j.biortech.2008.10.057. PMID 19119005