Ethanol production from cotton linter and waste of blue jeans textiles was investigated. In the best case,
alkali pretreatment followed by enzymatic hydrolysis resulted in almost complete conversion of the cotton
and jeans to glucose, which was then fermented by Saccharomyces cerevisiae to ethanol. If no pretreatment
applied, hydrolyses of the textiles by cellulase and b-glucosidase for 24 h followed by simultaneous
saccharification and fermentation (SSF) in 4 days, resulted in 0.140–0.145 g ethanol/g textiles, which was
25–26% of the corresponding theoretical yield. A pretreatment with concentrated phosphoric acid prior to
the hydrolysis improved ethanol production from the textiles up to 66% of the theoretical yield. However,
the best results obtained from alkali pretreatment of the materials by NaOH. The alkaline pretreatment of
cotton fibers were carried out with 0–20% NaOH at 0 C, 23 C and 100 C, followed by enzymatic hydrolysis
up to 4 days. In general, higher concentration of NaOH resulted in a better yield of the hydrolysis,
whereas temperature had a reverse effect and better results were obtained at lower temperature. The
best conditions for the alkali pretreatment of the cotton were obtained in this study at 12% NaOH and
0 C and 3 h. In this condition, the materials with 3% solid content were enzymatically hydrolyzed at
85.1% of the theoretical yield in 24 h and 99.1% in 4 days. The alkali pretreatment of the waste textiles
at these conditions and subsequent SSF resulted in 0.48 g ethanol/g pretreated textiles used.
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