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Indexed by:期刊论文

Date of Publication:2018-10-02

Journal:SEPARATION AND PURIFICATION TECHNOLOGY

Included Journals:SCIE

Volume:204

Page Number:133-140

ISSN No.:1383-5866

Key Words:Ionic liquids; Sugaring-out extraction; Salting-out extraction; Succinic acid; Ionic liquid recycling

Abstract:In this study, ionic liquids-based salting-out extraction and sugaring-out extraction were developed to extract succinic acid. Among these five investigated ionic liquids, the ionic liquid with BF4 and OTF- anion showed the ability to form two phases not only with glucose but also with salts. However, the ionic liquid with Br- anion cannot form aqueous two-phase system with glucose, but with salts. Relatively high extractabilities were obtained by ILs-based salting-out extraction systems compared to sugaring-out systems. The extraction efficiency values ranging between 47% and 86% were obtained when succinic acid concentration increased from 5 g/L to 70 g/L in [Bmim]BF4/(NH4)(2)SO4 systems. It was implied that succinic acid concentration was a key factor in ILs-based salting-out extraction system. Compared to salting-out extraction, sugaring-out extraction was more suitable for succinic acid separation due to the bottom phase reutilization to achieve coupling of fermentation and separation. The distribution behavior of succinic acid in [Bmim]BF4/glucose sugaring-out extraction system depends on not only the concentrations of ionic liquid and glucose, but also the pH. The partition coefficient (2.53) and recovery (75.96%) of succinic acid were obtained by a sugaring-out system consisting of 45% (w/w) [Bmim]BF4 and 30% (w/w) glucose at pH 2.0. Moreover, to support the applicability of ILs-based sugaring-out extraction for SA separation, the most prominent systems were further tested with actual fermentation broth. The extraction efficiencies were 73.71% and 72.53% for filtered and unfiltered fermentation broth, respectively. The remarkable results obtained in this work support the establishment of IL-based sugaring-out extraction as a sound basis of greener cost-effective strategies with a substantial reduction in the environmental footprint and economical issues.