title: Lignin dissolution in dialkylimidazolium-based ionic liquid-water mixtures.
abstract: Lignin dissolution in dialkylimidazolium-based ionic liquid (IL)-water mixtures (40wt%-100wt% IL content) at 60°C was investigated. The IL content and type are found to considerably affect lignin solubility. For the IL-water mixtures except 1-butyl-3-methylimidazolium tetrafluoroborate ([C4C1im]BF4), the maximum lignin solubility can be achieved at 70wt% IL content. Lignin solubility in IL-water mixtures with different cations follows the order 1-butyl-3-methylimidazolium ([C4C1im](+))>1-hexyl-3-methylimidazolium ([C6C1im](+))>1-ethyl-3-methylimidazolium ([C2C1im](+))>1-octyl-3-methylimidazolium ([C8C1im](+))>1-butyl-3-ethylimidazolium ([C4C2im](+))>1-butyl-3-propylimidazolium ([C4C3im](+)). For IL mixtures with different anions, lignin solubility decreases in the following order: methanesulfonate (MeSO3(-))>acetate (MeCO2(-))>bromide (Br(-))>dibutylphosphate (DBP(-)). Evaluation using the theory of Hansen solubility parameter (HSP) is consistent with the experimental results, suggesting that HSP can aid in finding the appropriate range of IL content for IL-water mixtures. However, HSP cannot be used to evaluate the effect of IL type on lignin solubility.
authors.affiliation: School of Light Industry and Chemical Engineering, Dalian Polytechnic University, Dalian 116034, China.
authors.forename: Yantao
authors.initials: Y
authors.lastname: Wang
authors.affiliation: School of Light Industry and Chemical Engineering, Dalian Polytechnic University, Dalian 116034, China. Electronic address: weilg@dlpu.edu.cn.
authors.forename: Ligang
authors.initials: L
authors.lastname: Wei
authors.affiliation: School of Light Industry and Chemical Engineering, Dalian Polytechnic University, Dalian 116034, China.
authors.forename: Kunlan
authors.initials: K
authors.lastname: Li
authors.affiliation: School of Light Industry and Chemical Engineering, Dalian Polytechnic University, Dalian 116034, China.
authors.forename: Yingchong
authors.initials: Y
authors.lastname: Ma
authors.affiliation: School of Light Industry and Chemical Engineering, Dalian Polytechnic University, Dalian 116034, China.
authors.forename: Ningning
authors.initials: N
authors.lastname: Ma
authors.affiliation: School of Light Industry and Chemical Engineering, Dalian Polytechnic University, Dalian 116034, China.
authors.forename: Shan
authors.initials: S
authors.lastname: Ding
authors.affiliation: School of Light Industry and Chemical Engineering, Dalian Polytechnic University, Dalian 116034, China.
authors.forename: Linlin
authors.initials: L
authors.lastname: Wang
authors.affiliation: School of Light Industry and Chemical Engineering, Dalian Polytechnic University, Dalian 116034, China.
authors.forename: Deyang
authors.initials: D
authors.lastname: Zhao
authors.affiliation: School of Light Industry and Chemical Engineering, Dalian Polytechnic University, Dalian 116034, China.
authors.forename: Bing
authors.initials: B
authors.lastname: Yan
authors.affiliation: School of Light Industry and Chemical Engineering, Dalian Polytechnic University, Dalian 116034, China.
authors.forename: Wenying
authors.initials: W
authors.lastname: Wan
authors.affiliation: School of Light Industry and Chemical Engineering, Dalian Polytechnic University, Dalian 116034, China.
authors.forename: Qian
authors.initials: Q
authors.lastname: Zhang
authors.affiliation: School of Light Industry and Chemical Engineering, Dalian Polytechnic University, Dalian 116034, China.
authors.forename: Xin
authors.initials: X
authors.lastname: Wang
authors.affiliation: School of Light Industry and Chemical Engineering, Dalian Polytechnic University, Dalian 116034, China.
authors.forename: Junmei
authors.initials: J
authors.lastname: Wang
authors.affiliation: School of Light Industry and Chemical Engineering, Dalian Polytechnic University, Dalian 116034, China.
authors.forename: Hui
authors.initials: H
authors.lastname: Li
mesh_terms: D000838:Anions / Q000737:chemistry; D007093:Imidazoles / Q000737:chemistry*; D052578:Ionic Liquids / Q000737:chemistry*; D008031:Lignin / Q000737:chemistry*; D008853:Microscopy; D008956:Models, Chemical; D012995:Solubility
chemical_list: D000838:Anions; D007093:Imidazoles; D052578:Ionic Liquids; D008031:Lignin
keywords: Dissolution; Ionic liquid–water; Lignin; Solubility parameter