title: Ethanol production from residual wood chips of cellulose industry: acid pretreatment investigation, hemicellulosic hydrolysate fermentation, and remaining solid fraction fermentation by SSF process.
abstract: Current research indicates the ethanol fuel production from lignocellulosic materials, such as residual wood chips from the cellulose industry, as new emerging technology. This work aimed at evaluating the ethanol production from hemicellulose of eucalyptus chips by diluted acid pretreatment and the subsequent fermentation of the generated hydrolysate by a flocculating strain of Pichia stipitis. The remaining solid fraction generated after pretreatment was subjected to enzymatic hydrolysis, which was carried out simultaneously with glucose fermentation [saccharification and fermentation (SSF) process] using a strain of Saccharomyces cerevisiae. The acid pretreatment was evaluated using a central composite design for sulfuric acid concentration (1.0-4.0 v/v) and solid to liquid ratio (1:2-1:4, grams to milliliter) as independent variables. A maximum xylose concentration of 50 g/L was obtained in the hemicellulosic hydrolysate. The fermentation of hemicellulosic hydrolysate and the SSF process were performed in bioreactors and the final ethanol concentrations of 15.3 g/L and 28.7 g/L were obtained, respectively.
authors.affiliation: Biochemical Engineering Department, Federal University of Rio de Janeiro, Rio de Janeiro, Rio de Janeiro 21945-970, Brazil.
authors.forename: Neumara Luci Conceição
authors.initials: NL
authors.lastname: Silva
authors.forename: Gabriel Jaime Vargas
authors.initials: GJ
authors.lastname: Betancur
authors.forename: Mariana Peñuela
authors.initials: MP
authors.lastname: Vasquez
authors.forename: Edelvio de Barros
authors.initials: Ede B
authors.lastname: Gomes
authors.forename: Nei
authors.initials: N
authors.lastname: Pereira
mesh_terms: D055162:Biocatalysis; D056804:Biofuels; D019149:Bioreactors; D001709:Biotechnology; D002482:Cellulose / Q000378:metabolism*; D000431:Ethanol / Q000378:metabolism*; D005285:Fermentation; D006868:Hydrolysis; D007220:Industrial Waste; D008031:Lignin / Q000737:chemistry / Q000378:metabolism; D010843:Pichia / Q000378:metabolism*; D011134:Polysaccharides / Q000378:metabolism; D012441:Saccharomyces cerevisiae / Q000378:metabolism*; D013464:Sulfuric Acids / Q000737:chemistry; D014934:Wood / Q000737:chemistry / Q000378:metabolism*; D014994:Xylose / Q000378:metabolism
chemical_list: D056804:Biofuels; D007220:Industrial Waste; D011134:Polysaccharides; D013464:Sulfuric Acids; D000431:Ethanol; C007916:hemicellulose; D002482:Cellulose; D008031:Lignin; D014994:Xylose; C033158:sulfuric acid