Authors: Hamid Amiri Keikhosro Karimi
Publish Date: 2015/07/16
Volume: 38, Issue: 10, Pages: 1959-1972
Abstract
A suitable pretreatment is a prerequisite of efficient acetone–butanol–ethanol ABE production from wood by Clostridia In this study organosolv fractionation an effective pretreatment with ability to separate lignin as a coproduct was evaluated for ABE production from softwood pine and hardwood elm ABE production from untreated woods was limited to the yield of 81 g ABE/kg wood and concentration of 55 g ABE/L Thus the woods were pretreated with aqueous ethanol at elevated temperatures before hydrolysis and fermentation to ABE by Clostridium acetobutylicum Hydrolysis of pine and elm pretreated at 180 °C for 60 min resulted in the highest sugar concentrations of 168 and 232 g/L respectively The hydrolysate obtained from elm was fermented to ABE with the highest yield of 1211 g/kg and concentration of 116 g/L The maximum yield of 879 g/kg was obtained from pine pretreated for 30 min at 150 °C Moreover structural modifications in the woods were investigated and related to the improvements The woody biomasses are suitable feedstocks for ABE production after the organosolv pretreatment Effects of the pretreatment conditions on ABE production might be related to the reduced cellulose crystallinity reduced lignin and hemicellulose content and lower total phenolic compounds in the hydrolysates
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