Bioethanol production from low-grade konjac powder via combination of alkaline and thermal pretreatments

Abstract

Combining alkaline and thermal pretreatments for the conversion of low-grade konjac powder to fermentable sugars was studied. After pretreatment, an enzyme hydrolysis procedure was applied with cellulase. The pretreatment and hydrolyzed liquids were used with Saccharomyces cerevisiae for the fermentation process in the batch system.  Analysis with a spectrometer revealed that the fundamental matter of low-quality konjac powder was severely degraded in order to enhance the fermentable sugars. Our investigation found that the alkaline combination thermal pretreatment produced the most reducing sugars. The impacts of several operational factors were examined. The highest alcohol content (3.551g/L), heating value (3570.27Cal/g) and energy values (17.15 MJ/kg) were achieved, this might be a very promising method of low-grade konjac powder use. Pretreatment of low-grade konjac powder for bioethanol production is highly advised due to its extremely low cost and high yield of reducing sugars and bioethanol.