title: Diluted phosphoric acid pretreatment for production of fermentable sugars in a sugarcane-based biorefinery.
abstract: The influence of time (8-24 min), temperature (144-186 °C) and phosphoric acid concentration (0.05-0.20%, w/v) on the pretreatment of sugarcane bagasse in a 20 L batch rotary reactor was investigated. The efficiency of the pretreatment was verified by chemical characterization of the solid fraction of the pretreated bagasse and the conversion of cellulose to glucose by enzymatic hydrolysis. Models representing the percentage of cellulose, hemicelluloses, lignin, solubilized hemicellulose and the enzymatic conversion of cellulose to glucose were predictive and significant. Phosphoric acid concentration of 0.20% at temperature of 186 °C, during 8 and 24 min, was shown to be very effective in solubilizing hemicellulose from sugarcane bagasse, reaching solubilization of 96% and 98%, respectively. Relatively low amounts of inhibitors were produced, and the phosphoric acid remaining in the hemicellulosic hydrolysate is at adequate levels for supplying phosphorous requirement during subsequent fermentation.
authors.affiliation: Laboratory of Biotechnological Processes, Federal University of Pernambuco, 50740-520 Recife, PE, Brazil.
authors.forename: Solange Maria
authors.initials: SM
authors.lastname: de Vasconcelos
authors.forename: Andrelina Maria Pinheiro
authors.initials: AM
authors.lastname: Santos
authors.forename: George Jackson Moraes
authors.initials: GJ
authors.lastname: Rocha
authors.forename: Ana Maria
authors.initials: AM
authors.lastname: Souto-Maior
mesh_terms: D000704:Analysis of Variance; D019149:Bioreactors; D001709:Biotechnology / Q000379:methods*; D002241:Carbohydrates / Q000096:biosynthesis*; D002482:Cellulose / Q000737:chemistry / Q000378:metabolism; D005285:Fermentation / Q000187:drug effects*; D005947:Glucose / Q000378:metabolism; D006868:Hydrolysis / Q000187:drug effects; D010756:Phosphoric Acids / Q000494:pharmacology*; D011134:Polysaccharides / Q000378:metabolism; D031786:Saccharum / Q000187:drug effects* / Q000378:metabolism*
chemical_list: D002241:Carbohydrates; D010756:Phosphoric Acids; D011134:Polysaccharides; C007916:hemicellulose; D002482:Cellulose; C027433:bagasse; C030242:phosphoric acid; D005947:Glucose