Adsorption of copper metal ion from aqueous solution by Nanoscale Zero Valent Iron (nZVI) supported on activated carbon

Copper is from one of the most important heavy metals, which adheres to the ecological system by harmful human activities. It is toxic, persistent, and non-biodegradable metal, which causes environmental pollution in both the atmosphere and aquatic environment. Copper pollution found in undesirable concentrations in industrial wastewaters especially from electronics industries, cooling systems and plating industry. Physical methods are mostly applied to remove Cu(II) including adsorption and membrane processes. Nanoparticles (e.g. nano zero valent iron (nZVI), carbon nanotubes, titanium dioxide nanoparticle) have been considered to be promising alternatives to conventional adsorbents. They have advantages by having more surface area and nano-sized pores, which helps to adsorb more molecules. In this study, in order to enhance adsorption by activated carbon and lower the cost of nanoparticle synthesis, nZVI is synthesized on activated carbon(AC-nZVI). It was investigated for its effectiveness in copper removal from aqueous solution. The effect of AC-nZVI dosage, pH and the initial concentration of Cu were investigated. Adsorption capacities are obtained for nZVI and AC-nZVI as 414 mg/g and 510 mg/g, respectively. 200mg/L AC-nZVI concentration was determined as sufficient for %96 removal rate. Langmuir isotherm gave the best fit and the maximum adsorption capacity according to Langmuir isotherm is calculated as 588,24 mg/g.