Association extraction for vitamin E recovery from deodorizer distillate by in situ formation of deep eutectic solvent

An innovative intensified vitamin E (VE) recovery process from the methylated oil deodorizer distillates (MODDs) was proposed, where VE was in situ transferred into a deep eutectic solvent (DES) with an organic salt. To design the process, the chlorine based quaternary ammonium salts were primarily investigated, and [N 4,4,4,4 ]Cl was selected as an association solvent which can efficiently form DES with α-tocopherol of the representative compound of VE. Based on the determined phase diagram of the DES freezing points, four phase regions were classified, and the effect of the [N 4,4,4,4 ]Cl/tocopherol ratio and temperature on the extraction performance and phase transformation was figured out. Moreover, an intensified association extraction process via in situ forming DES of α-tocopherol with [N 4,4,4,4 ]Cl was designed and validated by experiments. VE products were finally obtained from both model MODD (purity of 99.63%) and practical MODDs (purity of >79.18%), which verifies the excellent extraction efficiency for the proposed recovery method. © 2016 American Institute of Chemical Engineers AIChE J , 63: 2212–2220, 2017