Column reactors in fluidized bed configuration as intensification system for xylitol and ethanol production from napier grass (Pennisetum Purpureum)

Abstract

Currently, the modern concept biorefinery industries require a consolidated, robust and cost-effective bioprocess applied to multi-products manufacturing. In alignment, this work presents biomass pretreatment of Pennisetum purpureum grass and integrated developments for carbohydrates portions utilization as carbon source for xylitol and ethanol production in intensified process conducted in column reactor with fluidized bed configuration, homogenized simply by air insertion. Primarily, by using hemicellulosic portion from acid hydrolysis, xylitol production was evaluated in column fluidized bed reactor by using the novel-wild Brazilian yeast Candida Tropicalis UFMGBX12-a verifying YP/S and Qp of 0.26 g/g and 0.06 g/L.h, respectively. Forwardly, the remaining celulignin from the acid hydrolysis was subjected to alkaline pretreatment, followed by Semi-Simultaneous saccharification and Fermentation process, in an intensification approach performed in column fluidized bed reactor, applied to ethanol production by Scheffersomyces Shehatae UFMG-HM 52.2. Enzymatic hydrolysis of pretreated biomass comprised 90% of glucose yield in 72h of saccharification, while ethanol productivity of 0.21 g/L.h, was found in 24 h of fermentation process. These new developments conferred potential use of Pennisetum purpureum grass as carbon source for xylitol and ethanol production in column reactor towards sustainable intensification process implementation.