Investigation of the removal of diclophenac compound in twater by adsorption, coagulation and combined coaulation processes

In this study, the removal potential of Diclofenac compound, which is seen in drinking water sources and is generally produced as a micropollutant in the pharmaceutical industry, was investigated by adsorption, coagulation and combined coagulation processes on a laboratory scale. The water samples used in the experimental studies were taken from Ulutan Dam water and Ulutan drinking water treatment plant outlet.In experimental studies, single-walled carbon nanotube (SWNT), multi-walled carbon nanotube (MWNT) and powdered activated carbon (PAC) were used as adsorbent in adsorption processes. Alum was used as conventional coagulant in coagulation experiments.In particular, the highest diclofenac adsorption capacity was observed at acidic pH values. Different concentrations of NaCl (0.2, 0.4, 0.6, 0.8 and 1 mol/L) were used to determine the effect of ionic strength. In this study, the effects of pH and ionic strength on diclofenac adsorption capacity were investigated firstly.In the studies, it was determined that the diclofenac adsorbing capacity increased at concentrations above 0.6 M as ionic strength. According to the data obtained in the adsorption experiments, it was revealed that the adsorption mechanism that occurred was described by the Freundlich isotherm (R2 = 0.99).However, as a result of coagulation of water samples taken from Ulutan Dam water and Ulutan drinking water treatment plant effluent with conventional (Alum), it was determined that the removal of diclofenac was very low as 34.27% and 12.3%, respectively. On the other hand, it was determined that diclofenac removal occurred at high levels above 90% in combined coagulation processes performed with carbon nanotubes (SWNT, MWNT) and Alum.