Separation of phenols from oil via forming deep eutectic solvents (DES) is an efficient method. During the extraction

however

oil entrainment occurs

which influences the separation efficiency. In this work

the effects of added choline chloride (ChCl) amount

extraction temperature and concentration of straight-chain paraffin in model oil on the separation of phenols and oil entertainment in DES phase via forming DES were investigated. Toluene solution with 200 g·L-1 phenol was used as model oil and ChCl was used as extraction agent. The results showed that the separation efficiency of phenol from model oil increased with the increase of addition of ChCl and the increase of addition of ChCl could also reduce the entrainment of toluene in DES phase. The effect of temperature on the separation of phenol was not significant. The entrainment of toluene increased with the increase of temperature at low ratios of added ChCl to phenol; while it did not change significantly at high ratios of added ChCl to phenol. The entrainment of toluene was reduced with the increase of the concentration of aliphatic hydrocarbon. With ChCl as extraction agent

typically

the separation efficiency of phenol was 95% and the entrainment of toluene was 15% at 25℃ and mole ratio of ChCl to phenol of more than 0.6. Toluene could be removed completely within 60 min with nitrogen purging at 70℃.