Determination of Copper, Total Chromium and Silver in Impregnated Carbon

Abstract

Carbon samples were impregnated with ammonical solutions of silver salt alone and in combination with Cu and Cr salts. The impregnated samples were characterised for Cu, total Cr and Ag. Copper was extracted as CuCl/sub 2/ using concentrated HCl and Cr with NaOH. Silver was extracted from impregnated carbon using HNO3 and sodium thiosulphate (Na/sub 2/S/sub 2/O/sub 3/-5H/sub 2/0) and ashed impregnated carbons using aqua regia. The extracted metals in their solutions were quantitatively determined by titrimetric method and atomic absorption spectroscopy. The results were within acceptable limits of error. Sodium thiosulphate is recommended for extraction of Ag, as it accomplishes complete leaching of Ag faster than the other extracting agents.