OP-II-3

PP-III-113%. The filtrate after hydrolysis is subject to analysis for reducing saccharides. Themain parameters exammed in the experiments include hydrolysis reagent, acidsolution concentration, microwave power, temperature, and reaction time.Experimental results showed that waste cotton has relatively high cellulosecontent among all cellulosic biomass but is difficult to be hydrolyzed to reducingsaccharides by traditional hydrolysis methods. At room temperature, the hydrolysisefficiency is below 1% for different acid/base reagents and concentrations. With theassist of microwave, the hydrolysis rate and efficiency of waste cotton weresignificantly increased. Among the various experimental conditions, 30% HCl had thehighest hydrolysis efficiency for cotton fiber (38.1%). The next was 37% HCl(34.79%) and 40% H 2 SO 4 (27.88%). The optimal microwave temperature and timewere 110 °C (power 195W) and 10 min. The increase or decrease in microwavetemperature and time lowered the conversion efficiency due to incomplete or overdecompostion of cotton fiber. The reducing saccharide obtained from waste cotton bymicrowave hydrolysis can be fermented with the yeast Saccharomyces cerevisiaeand the ethanol yield was 4600 mg/l.References[1]. Ballesteros M.; Oliva J.M.; Negro M.J.; Manzanares P.; Ballesteros I. Ethanol from lignocellulosicmaterials by a simultaneous saccharification and fermentation process (SFS) with Kluyveromycesmarxianus CECT 10875. Process Biochemistry 2004, 39, 1843-1848.[2]. Dale B.E.; Henk L.L.; Shiang M. Fermentation of lignocellulosic materials treated by ammoniafreeze-explosion. Development of Industrial Microbiology 1984, 26, 223-233.[3]. Eichhorn S.J.; Baillie C.A.; Zafeiropoulos N.; Mwaikambo L.Y.; Ansell M.P.; Dufresne A.;Entwistle K.M.; Herrera-Franco P.J.; Escamilla G.C.; Groom L.; Hughes M.; Hill C.; Rials T.G.;Wild .M. Review: Current international research into cellulosic fibres and composites. Journal ofMaterial Science 2001, 36, 2107-2131.[4]. Saha B.C.; Iten L.B.; Cotta M.A.; Wu Y.V. Dilute acid pretreatment, enzymatic saccharificationand fermentation of wheat straw to ethanol. Process Biochemistry 2005, 40, 3693-3700.[5]. Iranmahboob J.; Nadim F.; Sharareh M. Optimizing acid-hydrolysis: a critical step for productionof ethanol from mixed wood chips. Biomass and Bioenergy 2002, 22, 401-404.[6]. Karimi K.; Emtiazi G; Taherzadeh M.J. Ethanol production from dilute-acid pretreated rice strawby simultaneous saccharification and fermentation with Mucor indicus, Rhizopus oryzae, andSaccharomyces cerevisiae. Enzyme and Microbial Technology 2006, 40, 138-144.[7]. Kaur P.P.; Arneja J.S.; Singh J. Enzymic hydrolysis of rice straw by crude cellulase fromTrichoderma reesei. Bioresource Technology 1998, 66, 267-269.[8]. Ohgren K.; Vehmaanpera J.; Siika-Aho M.; Galbe M. High temperature enzymatic prehydrolysisprior to simultaneous saccharification and fermentation of steam pretreated corn stover forethanol production. Enzyme and Microbial Technology 2007, 40, 607-613.AcknowledgementsThe authors gratefully acknowledge the National Science Council of R.O.C. (Taiwan) forthe financial support.460