Removal of ibuprofen and 4-isobutylacetophenone by non-dispersive solvent extraction using a hollow fibre membrane contactor

The removal of pharmaceutical pollutants such as ibuprofen (IBU) and its metabolite 4-isobutylacetophenone (4-IBAP) from water was investigated in a laboratory scale commercial hollow fibre membrane contactor by non-dispersive solvent extraction. The effects of water and solvent flow rates (92–474 ml/min) on the shell and tube side of the hollow fibre, respectively, were investigated. The hollow fibres were found to be very efficient in reducing the concentrations (10–110 μg/ml) of the pharmaceuticals in water by approximately 90% or greater within the first couple of minutes of experiment showing extremely fast kinetics. Faster removal was obtained when the organic phase flowed at a higher rate than the aqueous feed phase. The effect of aqueous phase pH on the removal was tested in the pH range 2–10. Ibuprofen removal was greatly affected by pH with close to 100% removal occurred at pH 2, and less than 20% removal occurred at pH 10. Removal of ibuprofen metabolite (4-isobutylacetophenone) was not affected by pH, and an average removal of 96% was achieved at both basic and acidic pH. The laboratory-scale experiments were conducted in both batch and once through modes. The mass transfer coefficients were also estimated under various operating conditions.

► Hollow fibre membrane was used for removal of pharmaceutical pollutants from water.
► Removal of ibuprofen (IBU) strongly depended on pH (∼100% removed at pH 2).
► IBU metabolite (4-isobutylacetophenone) removal (∼96%) was not affected by pH.
► The extraction increased with organic phase flow more than aqueous phase.
► The mass transfer coefficients were estimated under various operating conditions.