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

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 H-2 yield obtained was 801 ml H-2 g(-1) COD removal. Coulombic efficiency of 88 %, cathodic H-2 recovery of 58 % and total H-2 recovery of 51 % with an energy efficiency of 74 % were recorded.