Tuning Solute Partitioning Coefficients in a Biphasic Ionic Liquid/Water System to Facilitate Extraction of Lignin-Oxidized Aromatics

Jingyang Tian, Shiyu Fu, Chunhui Zhang, Lucian A. Lucia

Abstract


Extraction of aromatic substances obtained during oxidation of lignin with ionic liquids (ILs)-based molecular oxygen was investigated. It was found that virtually no aromatic substances could be directly extracted with organic solvent until water had been added to the system. The amount of extracted substances increased sharply with an increase in the molar ratio of water to ILs. The distribution constants of aromatic monomers between ILs/water and extracting solvent was obtained by Nernst partition function analysis. The constants fitted well to a second order exponential function model (ExpDec2), which indicated that the activity coefficients of reaction products between ILs and extracting solvent could be tuned by water addition. Among the seven organic solvents tested, ethyl acetate was the most effective, on account of its suitable polarity, while temperature more prominently affected extraction efficiency than time.

Keywords


Extraction of aromatics; Ionic liquid; Lignin oxidation; Partitioning coefficients

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Welcome to BioResources! This online, peer-reviewed journal is devoted to the science and engineering of biomaterials and chemicals from lignocellulosic sources for new end uses and new capabilities. The editors of BioResources would be very happy to assist you during the process of submitting or reviewing articles. Please note that logging in is required in order to submit or review articles. Martin A. Hubbe, (919) 513-3022, hubbe@ncsu.edu; Lucian A. Lucia, (919) 515-7707, lucian.lucia@gmail.com URLs: bioresourcesjournal.com; http://ncsu.edu/bioresources ISSN: 1930-2126