Optimal separation of phenol from model oils by forming deep eutectic solvents with quaternary ammonium salts

Overview: Effective Separation of Oxygen-, Nitrogen-, and Sulfur-Containing Aromatics in High-Temperature Coal Tar by Ionic Liquids and Deep Eutectic Solvents: Experimental and Computational

“…35 Although the cations with high symmetry and anions with higher electronegativity were favored to separate phenols from model oil mixtures, the phenol extraction yield of TEAC was rapidly decreased from 62.34% to 14.30% after regeneration times from 1 to 5. 36 This proves the saying of Hong Meng et al, "the stronger the extractive capability of the extractant is, the harder the back extraction of phenol by ether." 37 Amide compounds can also interact with phenolic compounds via the hydrogen bond, 38 whereas amide compounds with increasing steric hindrance of functionalized substituents can weaken the hydrogen bond between them.…”

“…Symmetric tetraethylammonium chloride (TEAC) have the best phenol extraction yield (99.9%) at a mole ratio of 4:5, 30 °C, and 30 min, but tetrabutylammonium chloride (TBAC) with the longer alkyl chain are completely miscible to the model oil . Although the cations with high symmetry and anions with higher electronegativity were favored to separate phenols from model oil mixtures, the phenol extraction yield of TEAC was rapidly decreased from 62.34% to 14.30% after regeneration times from 1 to 5 . This proves the saying of Hong Meng et al, “the stronger the extractive capability of the extractant is, the harder the back extraction of phenol by ether.”…”

A novel symmetrically structured protonated ionic liquids for alkane de‐aromatization

“…In addition, some extraction experiments also showed that the symmetrical structure has structural advantages. Tang and Liu 25 In general, the performance of ionic liquids in extracting aromatics mainly depends on the cationic part, with anions only as a secondary factor. 27 Therefore, if the symmetrical characteristics of anions can be introduced into cations, the extraction performance of ionic liquids will be further improved.…”

Thermodynamic Properties and Activity Coefficients at Infinite Dilution for Various Solutes in Deep Eutectic Solvent: Tetraethylammonium Chloride + Glycerol

“…DESs are a mixture of hydrogen bond donors (HBDs, such as ethylene glycol, lactic acid, and glycerol) and hydrogen bond acceptors (HBAs, such as choline chloride and tetraethylammonium chloride). The melting point of the DES is significantly lower than that of the constituent compound. , Due to their excellent physical and chemical properties, DESs have been widely used as separation agents in processes such as desulphurization, , denitrification, – alkanes/aromatics separation, , and separation of phenolic compounds from oil mixtures. , Tetraethylammonium chloride is a common HBD, which is used to prepared DESs for applications in gas absorption, coal tar separation, – dissolving metal oxides, alkane/aromatic separation, and so forth.…”