(395as) Kinetic Studies for the Removal of Copper From Industrial Wastewater Using Activated Neem (Azadirachta indica) Bark

Water pollution from the industrial effluent containing toxic heavy metals is increasing globally. Environmental regulations for the drinking water are becoming more and more stringent. There is a need to develop an effective technique to process the industrial wastewater containing toxic metals before releasing into the water bodies. Cu(II) is one of the heavy metals used in a number of industries such as plating, electrolysis, metal cleaning, etc. A number of processes such as chemical precipitation, adsorption, solvent extraction, etc. are available for the treatment of industrial wastewater for the removal of Cu(II). Adsorption is proven to be an efficient technique at large flow rates and higher metal concentrations.

In the present study, a low cost adsorbent is developed using the neem bark. The neem bark is activated by proper chemical and physical treatment and is being used as an adsorbent for the Cu(II) removal. The kinetic studies for Cu(II) removal are carried out by varying the initial concentration of Cu(II) from 50 to 200 mg L^-1. The equilibrium time for the removal of Cu(II) using activated neem bark as an adsorbent is estimated to be about 40 hours. Pseudo first order and Second order kinetic model are tested and found that Second order model best describes the adsorption of Cu(II) from aqueous solution. Weber & Moris and Boyd model are used for the determination of mass transfer mechanism during the adsorption process. It is found that both are satisfactorily fitting with the experimental results. This confirms that the process is dependent on both, the film diffusion and intraparticle diffusion mechanisms.