Study of the Liquid–Liquid Equilibrium and Extraction Properties of Deep Eutectic Solvents Based on Choline Chloride for the Separation of the Ethanol–Ethyl Formate System for Potential Use in Biofuel Production

Abstract

The separation of the azeotropic mixture ethanol−ethyl formate by various deep eutectic solvents (DESs) based on choline chloride was investigated. The liquid−liquid equilibria (LLE) for the systems ethanol− ethyl formate−DES were studied at 293.15 and 313.15 K and atmospheric pressure. 1 H NMR spectroscopy was used for the quantity analysis system under study. Density and dynamic viscosity were measured for the investigated DESs in the temperature range 293.15−323.15 K. The efficiency of separation of the system ethanol−ethyl formate by the DESs formed by choline chloride with various hydrogen bond donors (glycerol, urea, glutaric acid, and ethylene glycol) was evaluated by calculating the distribution coefficients and selectivity values. Dependences of the obtained selectivity values on ethanol mass fractions were discussed. A comparison of these data with the separation efficiency of other ethanol−ester systems by the same DESs was made. A correlation of experimental LLE data by the nonrandom two-liquid (NRTL) equation was carried out. Calculated data showed a good agreement with experimental compositions.

Effect of Deep Eutectic Solvents Based on Choline Chloride as Extractants on the Separation of the 1-Butanol–1-Butyl Formate System: Experimental Study and Comparative Analysis

“…Dependences of the selectivity values ( S ) on alcohol mass fraction in the systems: (a) 1-butanol–1-butyl formate–DES (ChCl/Glu) (blue solid circle) at 313.15 K, 1-propanol–1-propyl formate–DES (ChCl/Glu) (pink solid up-triangle) at 313.15 K, and ethanol–ethyl formate–DES (ChCl/Glu) (green solid tilted square) at 313.15 K; (b) 1-butanol–1-butyl formate–DES (ChCl/Glu) (blue solid circle) at 313.15 K, 1-butanol–1-butyl acetate–DES (ChCl/Glu) (pink open up-triangle) at 313.15 K, and 1-butanol–1-butyl propionate–DES (ChCl/Glu) (green open tilted square) at 313.15 K …”

New Experimental Results and Comparative Analysis of the Efficiency of Separation of Propyl Propionate and Propyl Formate from Propanol Using Deep Eutectic Solvents Based on Choline Chloride

“…Dependences of the selectivity values on the mass fraction of alcohol in systems: 1-propanol–1-propyl formate–DES (ChCl/EG) at 293.15 K (◯blue open circle) and 313.15 K (●blue solid circle), ethanol–ethyl formate–DES (ChCl/EG) at 293.15 K (◯green open circle) and 313.15 K (●green solid circle), 1-propanol–1-propyl formate–DES (ChCl/Gl) at 293.15 K (◯red open circle) and 313.15 K (●red solid circle) and ethanol–ethyl formate–DES (ChCl/Gl) at 293.15 K (◯pink open circle) and 313.15 K (●pink solid circle) …”

Experimental and Mechanistic Investigation of Amide-Based Deep Eutectic Solvents for Quinoline Extraction and Separation from Wash Oil

“…A significant amount of research has been conducted on the application of DESs for nitrogen removal from fuel oils, which provides a theoretical basis for further investigation of DES-based separation processes for quinolines from washed oils. − The group of Naik synthesized DESs by combining methyltriphenylphosphonium bromide (MTBP) with a specific hydrogen bond donors (HBDs) and investigated their effect on toluene and quinoline removal. Their work showed that these DESs had relatively lower selectivity for toluene compared to that for quinoline.…”