Herein, six ionic liquids (ILs) with different cations and the same anion of acetate (Ac−) were used to dissolve arabinoxylan. These ILs included N-methylimidazolium acetate (HmimAc), 1-ethyl-3-methylimidazolium acetate (EmimAc), 1-hydroxyethyl-3-methylimidazolium acetate (HOemimAc), 1-propyl-3-methylimidazolium acetate (PrmimAc), 1-allyl-3-methylimidazolium acetate (AmimAc), and 1-butyl-3-methylimidazolium acetate (BmimAc). The solubilities of arabinoxylan in these ILs were determined, and the dissolution mechanism was explained using 1H and 13C NMR techniques. The solubilities of arabinoxylan in the ILs were in the order: BmimAc > EmimAc > AmimAc > PrmimAc > HOemimAc > HmimAc. Both the cation and Ac− played an important role in the solubilization of arabinoxylan, but Ac− performed the major factor. The structure of cation greatly affected the hydrogen bond accepting ability of Ac−. Increasing the mass ratio of arabinoxylan to ILs resulted in stronger hydrogen bond between arabinoxylan and the ILs. Both the solubility and the strength of hydrogen-bonding interaction between arabinoxylan and the ILs decreased in the recycled ILs because of the impurities remained.
Bibliographical noteFunding Information:
This work was financially supported by the National Natural Science Foundation of China (No. 21666022 ). Appendix A
© 2019 Elsevier Ltd
- Hydrogen bond
- Imidazolium ionic liquid
PubMed: MeSH publication types
- Journal Article