Journal of Chemical Thermodynamics, Vol.125, 41-49, 2018
The aqueous biphasic system based on cholinium ionic liquids and nonionic surfactant and its application for triazine-based herbicides extraction
Aqueous biphasic systems (ABS) based on the surfactant (triton x-100, Tr) and cholinium ionic liquids were developed for the extraction of three herbicides (simetryn, prometryn, and atrazine). The influence of the phase compositions and temperature on the formation of the ABS was investigated. The biphasic region of the ABS decreased with the longer carbon chain of the anions in ILs, while increased with the higher temperature. The partitioning behaviour of the selected herbicides using the (Tr + choline acetate [Ch][Ac] + water) ABS was studied, and the analytes mainly concentrated the surfactant-rich phase. The partition coefficients of the herbicides decreased with increasing mass fractions of Tr, while increased with the higher concentrations of [Ch][ Ac], which means that salting-out ability of the IL played the important role on the system formation. The developed ABS is a promising method considering its simple operation, mild condition and biocompatibility without using any organic solvent during the extraction process. (C) 2018 Elsevier Ltd.
Keywords:Aqueous biphasic system;Cholinium ionic liquid;Partition coefficient;Phase diagram;Triazine-based herbicide