Study On Removal Of Ibuprofen From Water By Modified Activated Carbon

Ibuprofen is a common nonsteroidal anti-inflammatory drug that produced and discharged in a large amounts.At present,the presence of ibuprofen and its degradation products has been detected in the surface water of each country,which has a serious impact on the aquatic organisms and also has potential h arm to the human body.Activated carbon adsorption is one of the most commonly used advanced treatment technologies in drinking water plants in China.This paper explored the adsorption of ibuprofen by microwave modified activated carbon.The modified activated carbon was modified by different modification techniques,and the modified carbon with the best effect of removing ibuprofen was selected.We will explore the factors that affecting ibuprofen adsorption with the best modified carbon,and the adsorption kinetics,adsorption isotherm,and adsorption mechanism were explored.The modification methods of six kinds of activated carbon were studied:direct microwave modification,microwave modification under nitrogen,nitric acid modification,direct nitric acid-microwave modification,nitric acid-microwave modification with nitrogen and nitric acid-microwave modification.The effects of microwave power,microwave time and nitric acid concentration on the modification were investigated.The result is that we obtained the best modified carbon which under the protection of nitrogen,nitrogen aeration rate of 0.06m³/h,microwave power P=600W,microwave time t=5min.The static adsorption experiments of ibuprofen with modified carbon showed that the optimal a dsorption p H was 5,under this condition,the dosage of carbon was 0.2g/L and the removal rate of ibuprofen at initial concentration of 2mg/L was 88.40%,18.37%more than the original carbon.Kinetic studies show that the adsorption of ibuprofen on the modi fied carbon conforms to the quasi-second-order kinetic model,and adsorption reaches equilibrium at 720 min.Thermodynamic studies show that the adsorption of ibuprofen on modified carbon conforms to the Langumir adsorption isotherm,and the adsorption capacity increases with the increase of temperature.Thermodynamic parameters show that adsorption of ibuprofen on modified carbon is a spontaneous and endothermic process.The surface of the modified carbon was characterized by Boehm titration and zero charge titration.The results showed that the number of acidic groups such as carboxyl groups on the surface of modified carbon?except nitric acid modified and immersed nitric acid-microwave modified?decreased,the number of basic groups increase,zero charge p H_PZC higher than the original carbon and showed alkaline,indicating that non-polar carbon modified enhanced adsorption of non-polar organic removal efficiency.The microwave treatment of activated carbon has a potential application prospect for the removal of ibuprofen in water.