ADSORPTION OF HEAVY-METALS FROM AQUEOUS-SOLUTIONS ONTO ACTIVATED CARBON IN SINGLE CU AND NI SYSTEMS AND IN BINARY CU-NI, CU-CD AND CU-ZN SYSTEMS

Single copper and nickel adsorption from aqueous solutions onto a gran ular activated carbon is reported. Metal removals increase on raising pH and temperature, and decrease on raising the initial metal concentr ation at constant carbon dose. The adsorption processes are modelled u sing the surface complex formation (SCF) Triple Layer Model (TLM) with an overall surface bidentate species. A dependence of the SCF constan t on pH, initial molar metal/carbon ratio and temperature is observed, and a correlation for log K-ads, is determined. The SCF model success fully predicts copper and nickel removals in single metal solutions. A dsorption in the binary metal systems copper-nickel, copper-cadmium an d copper-zinc is also reported, showing competitive adsorption effects .