Xylose and hemicellulose release on sugarcane bagasse pretreatments using citric acid.

Different conditions of sugarcane bagasse pretreatment were evaluated using citric acid, considering in further analysis the combined severity factor. Temperature, time and citric acid concentration were used as input variables. In a Gas Chromatographer Perkin Elmer-Clarus 400, the levels of xylose, glucose and hemicellulose were determinate. Initial recovery rate are also determinate for each pretreatment condition in addition to combined severity factor. The linearity was demonstrated between: the release of xylose and hemicellulose, the xylose and initial material recovery and between hemicellulose and combined factor of severity. Linear correlation coefficients were higher than 0.75 in all cases, with statistic significance greater than 95%. Three empirical models are reported that were adjusted to predict the release of xylose, hemicellulose and initial material recovery.