Determination of Trace Elementsin Ground Water by two Preconcentration Methods Using Atomic Absorption Spectrometry

Abstract

This is a comparative study between two different methods of preconcentration done to separate the trace elements Cadmium, Nickel, Chromium, Manganese, Copper, Zinc and Lead in drinking (ground) water samples taken from different locations in Gezira State, Central Sudan (The map); these methods are (Coprecipitation) with Aluminium Hydroxide and by Ammonium Pyrrolidine Dithiocarbamate (APDC) using Methyl Isobutyl Ketone (MIBK) as an organic solvent; and subsequent analysis by Atomic Absorption Spectrometry (AAS) for both methods. The result of the comparison showed the superiority of the (APDC) coprecipitation method over the Aluminium Hydroxide coprecipitation method in the total percentage recoveries of the studied trace elements in drinking (ground) water samples; such results confirm previous studies. This study also involves direct analysis of these water samples by Atomic Absorption Spectrometry to determine the concentrations of trace elements Cadmium, Nickel, Chromium, Manganese, Copper, Zinc and Lead and compare it to the corresponding guide line values described by the World Health Organization and the maximum concentrations of trace elements in drinking water permitted by the Sudanese Standards and Metrology Organization (SSMO), where the concentrations of some elements in some samples were found to be different than the described values by both of the organizations. The study includes a trial to throw light on the effect of the proximity of the water samples sources to the Blue Nile river on its trace elements concentrations; no relation was proved to exist in that respect