title: Specific lignin precipitation for oligosaccharides recovery from hot water wood extract.
abstract: Hot water extraction is an important strategy of wood fractionation, by which the hemicelluloses can be separated for value-added products, while the residual solid can still be processed into traditional wood products. In this study, a combined process consisting of specific lignin precipitation and dialysis was proposed to recover hemicellulosic oligosaccharides (OS) from hot water extract (HWE). The results showed that polyaluminium chloride (PAC) precipitation was highly specific to large molecular lignin, leading to 25.1% lignin removal with negligible OS loss through charge neutralization mechanism. The separation was further enhanced by dialysis, reaching 37.6% OS recovery from HWE with remarkable purity of 94.1%. By the proposed process, 56.36 g OS, mainly xylooligosaccharides with two fractions of 5.2 and 0.51 kDa was recovered from one kg dried wood. This process can be envisaged as a great contribution to wood biorefinery.
authors.affiliation: Key Laboratory of Paper Science & Technology of Ministry of Education, Qilu University of Technology, Jinan 250353, China.
authors.forename: Xiaoqian
authors.initials: X
authors.lastname: Chen
authors.affiliation: Key Laboratory of Paper Science & Technology of Ministry of Education, Qilu University of Technology, Jinan 250353, China.
authors.forename: Zhaojiang
authors.initials: Z
authors.lastname: Wang
authors.affiliation: Key Laboratory of Paper Science & Technology of Ministry of Education, Qilu University of Technology, Jinan 250353, China.
authors.forename: Yingjuan
authors.initials: Y
authors.lastname: Fu
authors.affiliation: Key Laboratory of Paper Science & Technology of Ministry of Education, Qilu University of Technology, Jinan 250353, China.
authors.forename: Zongquan
authors.initials: Z
authors.lastname: Li
authors.affiliation: Laboratory of Organic Chemistry, Taishan University, Taian 271021, China. Electronic address: qmh@spu.edu.cn.
authors.forename: Menghua
authors.initials: M
authors.lastname: Qin
mesh_terms: D000536:Aluminum Hydroxide / Q000494:pharmacology; D011232:Chemical Precipitation; D003956:Dialysis; D006358:Hot Temperature; D006863:Hydrogen-Ion Concentration / Q000187:drug effects; D008031:Lignin / Q000302:isolation & purification*; D009844:Oligosaccharides / Q000302:isolation & purification*; D010316:Particle Size; D032107:Populus / Q000187:drug effects; D055672:Static Electricity; D014867:Water / Q000494:pharmacology*; D014934:Wood / Q000187:drug effects*
chemical_list: D009844:Oligosaccharides; D014867:Water; C016213:aluminum oxychloride; D000536:Aluminum Hydroxide; D008031:Lignin
keywords: Hot water extraction; Oligosaccharides; Polyaluminium chloride; Specific lignin precipitation