title: Comparison of hemicellulose extracts from two pulping woodchips with green liquor followed by scale-up pre-hemicellulose extraction.
abstract: This study investigates the effects of different pre-pulping extraction conditions on two types of raw material, hardwood oak chips and softwood pine chips. The chips were air-dried, and 2-g samples were extracted in a Dionex ASE-200 with alkaline solutions of a partially recovered form of kraft pulping liquor called green liquor (GL). The GL was applied at different alkali charges of 0-5 % on dry wood weight. The extractions were performed at various H-factors from 500 to 1100 with temperatures ranging from 170 to 190 °C. As the alkali charge decreased, the amount of monosaccharides in the extracts increased while the remaining solids decreased. The highest xylose + mannose + galactose (xmg) concentrations (12.73 and 11.12 g/L for extracts derived from hardwood and softwood, respectively) were detected with a hot water extraction (GL 0 %) at 180 °C and an H-factor of 900. However, low amounts of remaining solids were obtained under these conditions (65.77% and 74.42%, for hard- and soft woods, respectively). We also performed an extraction that was scaled-up in a 1-L Parr reactor with 80 g of woodchips under pre-optimized condition through ASE-200. In this condition, the xmg and acetic acid concentrations of the hardwood extracts were 9.74 and 9.94 g/L, respectively, whereas their concentrations in the softwood extracts were 3.59 and 3.76 g/L, respectively.
authors.affiliation: Department of Chemical Engineering and Research Center of Chemical Technology, Hankyong National University, Anseong, Gyeonggi-do, 456-749, Republic of Korea.
authors.forename: Seong Ju
authors.initials: SJ
authors.lastname: Kim
authors.forename: Byung Hwan
authors.initials: BH
authors.lastname: Um
mesh_terms: D001709:Biotechnology / Q000295:instrumentation / Q000379:methods*; D006868:Hydrolysis; D028223:Pinus / Q000737:chemistry*; D011134:Polysaccharides / Q000302:isolation & purification*; D029963:Quercus / Q000737:chemistry*; D014934:Wood / Q000737:chemistry*
chemical_list: D011134:Polysaccharides; C007916:hemicellulose