Choline chloride based deep eutectic solvents as extraction media for separation of n-hexane–ethanol mixture

Abstract Two different choline chloride based deep eutectic solvents (DES) were tested for the separation of azeotropic mixture of n -hexane and ethanol via liquid-liquid extraction. The simplest mixtures of choline chloride with dibasic acids: oxalic (DES1) or malonic (DES2) with molar ratio 1:1 were used. The selected DESs were characterized by differential scanning calorimetry (DSC). Extraction experiments were conducted with pseudo-ternary mixtures n -hexane–ethanol–DES. Tie-lines were obtained at temperatures 293.15 K, 313.15 K and atmospheric pressure. The extraction performance of DES was characterized with solute distribution coefficients and values of selectively for ethanol. It has been shown that the most successful component for the separation of a mixture of n -hexane-ethanol is water. It was found that DES1 is more effective then DES2 for extraction of ethanol. The higher efficiency of separation of DES as compared to conventional ionic liquids (IL) makes it possible to consider them as an alternative promising solution in the separation of multicomponent mixtures. Experimental data was fitted using the nonrandom two liquids (NRTL) model.

[1]  Pedro D. A. Bastos.  Separation of azeotropic mixtures using high ionicity ionic liquids , 2015 .

[2]  Qinqin Zhang,et al.  Separation of 2-propanol and water azeotropic system using ionic liquids as entrainers , 2016 .

[3]  Maaike C. Kroon,et al.  A new low transition temperature mixture (LTTM) formed by choline chloride + lactic acid : characterization as solvent for CO2 capture , 2013 .

[4]  Raymond K. Rasheed,et al.  Deep eutectic solvents formed between choline chloride and carboxylic acids: versatile alternatives to ionic liquids. , 2004, Journal of the American Chemical Society.

[5]  A. Wells,et al.  On the Freshwater Ecotoxicity and Biodegradation Properties of Some Common Ionic Liquids , 2006 .

[6]  Qinqin Zhang,et al.  Separation of ethyl acetate and 2-propanol azeotropic mixture using ionic liquids as entrainers , 2016 .

[7]  Isabel M. Marrucho,et al.  Deep Eutectic Solvents as Azeotrope Breakers: Liquid-Liquid Extraction and COSMO-RS Prediction , 2016 .

[8]  M. Kroon,et al.  Low transition temperature mixtures (LTTMs) as novel entrainers in extractive distillation , 2015 .

[9]  J. Prausnitz,et al.  LOCAL COMPOSITIONS IN THERMODYNAMIC EXCESS FUNCTIONS FOR LIQUID MIXTURES , 1968 .

[10]  Mert Atilhan,et al.  Deep Eutectic Solvents: Physicochemical Properties and Gas Separation Applications , 2015 .

[11]  B. González,et al.  Ethanol extraction from its azeotropic mixture with hexane employing different ionic liquids as solvents , 2012 .

[12]  Catarina Florindo,et al.  Insights into the Synthesis and Properties of Deep Eutectic Solvents Based on Cholinium Chloride and Carboxylic Acids , 2014 .

[13]  Mohd Ali Hashim,et al.  Phase equilibria of toluene/heptane with deep eutectic solvents based on ethyltriphenylphosphonium iodide for the potential use in the separation of aromatics from naphtha , 2013 .

[14]  B. González,et al.  Ionic liquids as solvents to separate the azeotropic mixture hexane/ethanol , 2013 .

[15]  M. Kroon,et al.  Aliphatic + ethanol separation via liquid-liquid extraction using low transition temperature mixtures as extracting agents , 2015 .

[16]  H. Matsuura,et al.  (Liquid + liquid) equilibria of (water + ethanol + n-hexane) from 0.1 to 200 MPa at 298.15 K , 1988 .

[17]  J. Esperança,et al.  Alkylsulfate-based ionic liquids to separate azeotropic mixtures , 2010 .

[18]  M. Hashim,et al.  Potential applications of deep eutectic solvents in nanotechnology: Part II , 2015, Chemical Engineering Journal.