Paper Title
Statistical Optimization for Alkali Extraction of Xylan from Sugarcane Bagasse by Surface Response Methodology

Abstract
Xylan extraction from sugarcane bagasse was studied in lab-scale with NaOH and KOH solutions enhanced by thermal autoclaving and statistical optimization using response surface methodology. The raw sugarcane bagasse sample was analyzed for chemical components; cellulose, hemicellulose and lignin of 49.9, 28.6% and 21.5%, respectively. Then the extraction reaction was individually carried out with NaOH and KOH solutions by using statistical experimental design. Three independent variables, namely alkali concentration, extraction temperature and extraction time were investigated. First, NaOH extraction; the maximum experimental extracted xylan of 0.94 g (65.7% of original xylan) was obtained with NaOH solution concentration of 1.75 M, extraction temperature of 75°C and extraction time of 25 min. While KOH extraction; the maximum experimental extracted xylan of 0.78 g (54.5% of original xylan) was obtained with KOH solution concentration of 0.5 M, extraction temperature of 75°C and extraction time of 40 min. The extraction efficiency (%Ee) of xylan extraction from sugarcane bagasse by NaOH and KOH solutions was 18.8 and 15.6%, respectively. Keywords - Xylan, Sugarcane Bagasse, Alkali Extraction, Response Surface Methodology