Lignocellulosic ethanol production employing immobilized Saccharomyces cerevisiae in packed bed reactor. (December 2016)

• Record Type: Journal Article
• Authors: Mishra, Abhishek; Sharma, Ajay K.; Sharma, Sumit; Bagai, Rashmi; Mathur, Anshu S.; Gupta, Ravi P.; Tuli, Deepak K.
• Is Part Of: Renewable energy. Volume 98(2016)
• Page Start: 57
• Page End: 63
• Publication Date: 2016-12
• Subjects: Ethanol fermentation -- Immobilization -- Calcium alginate beads -- PBR -- Saccharomyces cerevisiae; PBR packed bed reactor -- REH rice straw enzymatic hydrolysate -- NB normal beads -- EHB immobilized alginate beads with extra hardening; Renewable energy sources -- Periodicals; Power resources -- Periodicals; Énergies renouvelables -- Périodiques; Ressources énergétiques -- Périodiques; 333.794
• DOI: 10.1016/j.renene.2016.02.010
• Languages: English
• ISSNs: 0960-1481

Abstract

Abstract: Most of ethanol production processes are limited by lower ethanol production rate and recyclability problem of ethanologenic organism. In the present study, immobilized co-fermenting Saccharomyces cerevisiae GSE1618 was employed for ethanol fermentation using rice straw enzymatic hydrolysate in a packed bed reactor (PBR). The immobilization of S . cerevisiae was performed by entrapment in Ca-alginate for optimization of ethanol production by varying alginic acid concentration, bead size, glucose concentration, temperature and hardening time. Remarkably, extra hardened beads (EHB) immobilized with S . cerevisiae could be used up to repeated 40 fermentation batches. In continuous PBR, maximum 81.82 g L −1 ethanol was obtained with 29.95 g L −1 h −1 productivity with initial glucose concentration of 180 g L −1 in feed at dilution rate of 0.37 h −1 . However, maximum ethanol concentration of 40.33 g L −1 (99% yield) with 24.61 g L −1 h −1 productivity was attained at 0.61 h −1 dilution rate in fermentation of un-detoxified rice straw enzymatic hydrolysate (REH). At commercial scale, EHB has great potential for continuous ethanol production with high productivity using lignocellulosic hydrolysate in PBR. Highlights: EHB were used up to 40 repeated fermentation batches with 97% ethanol yield. In continuous mode, 82 g L −1 ethanol with ≈30 g L −1 h −1 productivity was obtained. Using rice straw enzymatic slurry, ≈25 g L −1 h −1 ethanol productivity was observed. REH without detoxification makes ethanol production economical and sustainable.