Improvements in Use of Chelex-100 Resin for Determination of Copper, Cadmium and Iron in Sea Water

Abstract

Tests have been carried out for copper and iron to determine the capacity of Chelex-100 resin in its “sea form”, using a constant quantity of resin and variable volumes of sea water. For copper an asymptotic capacity curve is found analogous to the cadmium curve reported earlier, while for iron a maximum is observed. As Chelex-100 in its “sea form” appears useful for the determination of cadmium, but not for that of copper and iron, a preconcentration procedure utilising the Chelex-100 in its H⁻ form is proposed. Using batch equilibration and a practical sea water/exchanger ratio, good recoveries and low blank values were obtained. The method was tested for sea water reference material.