Abstract
This study was conducted to reduce the phenols concentration in produced water to meet the environmental regulatory limit. Three phenols namely phenol, 2-chlorophenol, and 4-nitrophenol were extracted individually from their aqueous solutions using emulsion liquid membranes prepared using kerosene as the membrane phase, combination of (Span 80) surfactant and a hydrophobic ionic liquid 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl) imide, [BMIM](+)[NTf2](-)-, and NaOH as the stripping agent in the inner phase of the W/O emulsions. Experiments were carried out to study the influence of three emulsion composition variables, namely the ionic liquid concentration, internal aqueous stripping phase to organic phase ratio (phi 1), and NaOH concentration in the internal phase, as well as three process parameters, emulsion to external aqueous feed phase ratio (f 2), mixing speed of feed solution, and the initial solute concentration in the feed on the rates of extraction of phenols. The emulsion stability time increases with an increase in the concentration of [BMIM](+)[NTf2](-) up to 0.3% v/v in emulsion. The removal efficiency of phenol from the feed solution with 30 ppm solute was 81% after 10 min and 78% after 30 min. On the other hand, the removal efficiency of both 2-chlorophenol and 4-nitrophenol was 91% after 10 min, and 95% and 98.5%, respectively, after 30 min of permeation under the most favorable operating conditions.