Effects of fertilizer application and dry/wet processing of Miscanthus x giganteus on bioethanol production

Abstract

The effects of wet and dry processing of miscanthus on bioethanol production using simultaneous saccharification and fermentation (SSF) process were investigated, with wet samples showing higher ethanol yields than dry samples. Miscanthus grown with no fertilizer, with fertilizer and with swine manure were sampled for analysis. Wet-fractionation was used to separate miscanthus into solid and liquid fractions. Dilute sulfuric acid pretreatment was employed and the SSF process was performed with saccharomyces cerevisiae and a cocktail of enzymes at 35°C. After pretreatment, cellulose compositions of biomass of the wet samples increased from 61.0-67.0% to 77.0-87.0%, which were higher than the compositions of dry samples. The highest theoretical ethanol yield of 88.0% was realized for wet processed pretreated miscanthus, grown with swine manure. Changes to the morphology and chemical composition of the biomass samples after pretreatment, such as crystallinity reduction, were observed using SEM and FTIR. These changes improved ethanol production.

Uses of miscanthus press juice within a green biorefinery platform

“…Due to the complete removal of hemicellulose during the pretreatment process, high enzymatic digestibilities were observed. High enzymatic digestibility and the use of a cocktail of enzymes for the SSF process resulted in high theoretical ethanol yields (Boakye-Boaten et al, 2016). As indicated earlier (Table 3), the mass of microorganisms harvested after aerobic growth in 90 % (v/v) MxG juice media was higher than that harvested after aerobic growth in the YM commercial media.…”

“…After mechanical pressing, the mass distribution of MxG was about 0.4 g/g of solid and 0.5 g/g of liquid (Boakye-Boaten et al, 2016). The total solid content of MxG press cake was 17.4 % of the total biomass, and the solid content of the juice was 0.1 % (Table 1).…”

Techno-economic analysis for the biochemical conversion of Miscanthus x giganteus into bioethanol

“…Multiple technological aspects of bioethanol production from Miscanthus have been studied in the recent literature, including improving pretreatment methods [21]- [26], enhancing enzymatic hydrolysis and microbial fermentation [24], [27], [28], boosting energy efficiency of the process [29], and understanding the chemical compositions of Miscanthus for better processing [30]- [32]. Economics literature on bioenergy from Miscanthus has focused on the costs of the feedstock production and delivery to processing plants [20], [33], [34], as well as the implications of large-scale Miscanthus production for markets and land use [35]- [38].…”

Green Biorefinery of Giant Miscanthus for Growing Microalgae and Biofuel Production

“…The mechanical press was largely effective in separating freshly harvested MxG into juice and cake with a percentage mass distribution of between 0.5 g/g of liquid and 0.5 g/g of solid [17]. The compositions of the separated MxG solid cake and juice are listed in Table 1.…”

“…The concentration of monomeric sugars, including cellobiose, glucose, arabinose and xylose in all liquid fractions as well as the concentration of ethanol were all determined using a Dionex Ultimate 3000 (UHPLC) (Thermo Fisher Scientific, Bannockburn, IL, USA) equipped with a Shodex Sugar SH 1218 ion exclusion column and a Shodex RI-101 refractive index detector [17]. The samples were analyzed using a UPLC-QTOF-MS system (ACQUITY UPLC-SYNAPT MS, Waters Corp., Milford, MA, USA).…”