Analysis of some trace elements with AAS after enrichment on XAD-2000 resin

SUMMARY Analysis of Some Trace Elements with AAS after Enrichment on XAD-2000 Resin The enrichment conditions of Cr, Co, Cu, Fe, Ni, Mn, Cd and Pb with Amberlit XAD-2000 resin, which have not been used in the enrichment of trace elements earlier, were investigated in the current study. After the trace quantities of the metals of interest were solved and chelated with APDC (ammonium pyrrolidine dithiocarbamate), recovery yield and optimization conditions were studied by passing the preparations through mini columns filled with XAD-2000 resin. Recovery conditions including pH; type, volume and concentration of eluent; quantity and size of resin; concentration of complexing agent; solution volume; effects of matrix constituents; solution flow rate through column; and resin capacity were studied. The effect of pH on recovery was studied in the pH range of 2 to 12. Among the metals studied, Cd could be recovered quantitatively, and Cu, Co, Ni and Pb could be recovered almost quantitatively at pH 2-7, while the recovery of Fe, Cr and more specifically Mn at this pH were found to be low. However, these metals showed 78-86% recovery at pH 12. pH 6 was selected for the optimization, and recovery yield for other conditions were investigated. Trace metals were quantitated with Flame Atomic Absorption Spectrometer. After the statistical analysis of the data collected was performed, mean recovery of 91.4-95.8 %, percent relative standard deviation of 2.1-6.1, confidence limits of 1.6-4.1, and detection limits of 11-38 mg/L were found. The accuracy of the method was tested with the well known method of extraction with MIBK and with the use of SLEW-2 sea water reference standard. The method was applied to the river waters of East Black Sea Region and some manganese salts. The metal concentrations were found to be 2.8-27.2, 1.0-3.4, 0.2-1.4, 1.2-4.8 and 2.5-14.0 ug/L in river waters, and 1.2-1.8, 0.5-0.9, 0.9-1.9, 0.4-0.6 and 6.3-7.4 (ig/g in manganese salts for Cu, Co, Cd, Ni and Pb respectively. Key Words: Enrichment, preconcentration, trace element, adsorption, XAD-2000 resin, atomic absorption spectroscopy, river water, manganese salts. VIII