Enzymatic Hydrolysis of Lignocellulosic Materials in Aqueous Media followed by Microbiological Synthesis of Bioethanol

Abstract

Enzymatic hydrolysis in aqueous media was studied using a lignocellulosic material (LCM) prepared from miscanthus and LCM prepared from oat covering (OC) as substrates to obtain bioethanol. LCM synthesis was a one-step processing of the feedstock with nitric acid (Pilot Plant of IPCET SB RAS). Commercially available enzymatic agents CelloLux-A and BrewZyme BGX were used for enzymatic hydrolysis in aqueous media at high initial concentrations (90 g/l) of the substrates. The yields of reducing substances (monosaccharides, mainly glucose) were established to equal 65,4 % and 73,3 % of the substrate weight for miscanthus LCM and OC, respectively. The composition of monosaccharides as products of biocatalytic decomposition of LCM was studied for the first time to show the predominant content of glucose. It was first time to synthesize bioethanol from LCM. The yield of bioethanol per unit of feedstock was 19,4 dal/t for miscanthus biomass and 16,2 dal/t for OC. A low methanol content (0,002–0,005 vol %) was characteristic of the experimental bioethanol samples.