Investigation of the abiotic removal of pharmaceutical matters in activated sludge waste water treatment process

In this study, the adsorption properties of the activated sludge on two antiinflammatory pharmaceuticals that are paracetamol and diclofenac have been investigated. Basic adsorption studies indicated that the paracetamol and diclofenac were adsorped by activated sludge. The removal efficiency for paracetamol changes between 53-69% and for diclofenac changes 36-86%. The results of the equilibrium experiments have been applied on Langmuir and Freundlich isotherm models and according to those results, both of adsorption of paracetamol by activated sludge (R=0.9987, Kf=2.5118, n=3.0998) and adsorption of diclofenac by activated sludge (R=0.9877, Kf=0.8692, n=2.6781) were fitted to Freundlich isotherm model. The kinetics of the adsorption were also investigated and for this purpose three kinetic models namely first order lagergren model, the second order model and a pseudo second order models have been investigated. It was found out that kinetics of both adsorption processes was best described by pseudo-second order model. The Gibbs free energies of both pharmaceuticals have been calculated and it was found out that for paracetamol ?G0=-0.8123 kJ/mol and for diclofenac ?G0=1.3718 kJ/mol. Key Words : Abiotic Removal, Pharmaceuticals, Paracetamol, Diclofenac, Kinetic.