Determination of copper, nickel and cadmium by FAAS after preconcentrationwith zinc-piperazinedithiocarbamate loaded on activated carbon by solid-phase extraction

A method was developed for the preconcentration of copper, nickel and cadmi um in water samples, prior to their determination by FAAS, using the Zn-pip erazinedithiocarbamate complex (ZnPDC) loaded on activated carbon. in this method, Cu, Ni and Cd in liquid phase quantitatively replaced zinc on a ZnP DC-activated carbon solid phase. Afterwards, the metals on the solid phase were easily eluted by Hg(II) solution into aqueous phase, and were measured by FAAS. The optimum experimental parameters such as pH, sample volume, an d effect of matrix ions for the preconcentration of the metals were investi gated. The range of Linearity 0-6, 0-5, 0-3 mu gml(-1), correlation coeffic ient 0.9981 0.996, 0.999, detection limits 15.7, 23.5, 11.8 ngml(-1) and de termination limits 136, 179, 98 ngml(-1) in final Hg(II) solution were obta ined for Cy Ni and Cd, respectively. The proposed method has been employed for the determination of Cu Ni and Cd in various standard metal alloys and natural water samples.