Enhanced Vitamin E Extraction Selectivity from Deodorizer Distillate by a Biphasic System: A COSMO-RS and Experimental Study

To enhance the extraction selectivity of vitamin E (VE) from the deodorizer distillate, a biphasic system with solvents of both organic chemical and the salt tetrabutylammonium chloride ([N4,4,4,4]Cl) was established. The organic solvent was tailored to extract the major component of deodorizer distillate (methyl linoleate), while the organic salt was designed to selectively extract VE by in situ forming a deep eutectic solvent. Three types of organic solvents, namely, ester, arene, and alkane, were analyzed by using the COSMO-RS model, and hexane, exhibiting stronger interaction with methyl linoleate and lower solubility of [N4,4,4,4]Cl, was screened and its suitability explained from the σ-profile and σ-potential points of view. The biphasic experiments demonstrated that the selectivity of VE by the one-pass extraction process was significantly enhanced by the biphasic system, and the important operation parameters of the dosage of solvent and initial concentration of VE were analyzed.