Optimization of Removal of Phenol from Aqueous Solution by Ionic Liquid‐Based Emulsion Liquid Membrane Using Response Surface Methodology

Abstract

AbstractResponse surface methodology was employed to optimize the removal of phenol from aqueous solution by ionic liquid (1‐butyl‐3‐methylimidazolium hexafluorophosphate dissolved in tributyl phosphate) based emulsion liquid membrane. A “minimum run resolution V” central composite design with six variables (surfactant concentration, internal phase concentration, emulsification time, internal to membrane phase ratio, stirring speed and external phase pH) was applied to optimize the process. The optimized conditions for maximum removal of phenol were a surfactant concentration – 4.95% (v/v), internal agent concentration – 0.298 N, emulsification time – 4.07 min, internal to membrane phase ratio – 0.93, stirring speed – 247 rpm and external phase pH – 5.91 respectively. The results showed good fits with the proposed statistical model for removal of phenol (R2 = 0.9833).