Design of a single chambered microbial electrolytic cell reactor for production of biohydrogen from rice straw hydrolysate

Abstract

Rice straw was pretreated using a microwave-assisted alkali pretreatment method. Cellulose recovery was approximately 82 %. This material was hydrolysed in an optimized enzymatic saccharification reaction using cellulase from Lysinibacillus sphaericus. This resulted in saccharification of 49 % of cellulosic biomass into glucose. A single chambered microbial electrolytic cell reactor of volume 2l was built using acrylic plastic sheets with graphite sheet as anode and a stainless-steel mesh as cathode. Shewanella putrefaciens was used as exoelectrogen to oxidize rice straw hydrolysate in the reactor for electrohydrogenesis. The maximum H2 yield obtained was 801 ml H2 g(-1) COD removal. Coulombic efficiency of 88 %, cathodic H2 recovery of 58 % and total H2 recovery of 51 % with an energy efficiency of 74 % were recorded.

Platform Study on the Development of a Nondetoxified Rice Straw Hydrolysate to Its Application in Lipid Production from Mortierella alpina

“…While cellulose is a linear homopolymer of β-D glucosic monomers hemicelluloses, potentially the second largest biological carbon reservoir after celluloses, are branched heteropolymers of pentoses (xylose and arabinose) and some hexoses (mannose, glucose, galactose). Cellulose and hemicelluloses upon saccharification, can release abundant fermentable sugars that can be processed and converted to diverse high-value microbial products such as hydrogen, ethanol, propanol, citric acid, phytate, surfactants, etc. − However, cellulosic accessibility for digestion (enzymatic or chemical) is confronted by two major challenges. First, the sugar monomers are entrapped in highly crystalline cellulosic cross-linked chains.…”