Kinetic and Thermodynamic Studies for Ciprofloxacin Hydrochloride Adsorption from Aqueous Solution on CuO Nanoparticles

Adsorption is the most versatile and widely used method for the removal of pollutants due to its high efficiency and ease of operation at large scale. In recent years nano metal oxides have been extensively used for the removal of pharmaceutical pollutants from waste water. In the present study, the adsorption behaviour of ciprofloxacin hydrochloride from aqueous medium, using CuO nanoparticles (synthesized by precipitation method)has been studied using batch experiments. The nanoparticles are characterized using X-Ray Diffraction, U.V and TEM. The average particle size, as determined from the XRD data, is 19.96 nm.The effects of initial drug concentration in the range 10-100mg/l, contact time 15165 mins.pH entire range and the effect of temperature in the range 25 0 –45 0 Con the adsorption capacity have been studied. Maximum removal 81.5% has been observed at pH 4 for a contact time of 135 min and drug concentration 100 mg/l, with an adsorbent dose of 100mg/10ml at temperature 298 K. Data obtained at optimum conditions have been subjected to isothermmodeling viz Freundlich, Langmuir, Temkin and Dubinin-Radushkevitch. The experimental data fits well to all the isotherm models with high correlation coefficient values.The experimental data fits to the first order rate equation and process follows first order kinetics. A study of intraparticle diffusion using the Morris Weber model shows that intraparticle diffusion occurs but is not the rate determining step. Thermodynamic parameters suggest the process to be exothermic and spontaneous with increased randomness at the solid solution interface.