Preconcentration of gold (III), palladium (II) and ruthenium(III) with dithio-carbamate-chitin

Dithiocarbamate-chitin (DTC-chitin) has been synthesized and used for concentration of gold (III), palladium (II) and ruthenium (III) from an acidic solution. The former two metals were quantitatively retained on the polymer from 6 M hydrochloric acid even at a high flow rate(15 ml min-1), in contrast to only 80% retention for ruthenium in a narrow pH range, 3.0-4.5. Gold retained on the polymer could be eluted with 1 M nitric acid containing 5% thiourea, while palladium with 1.6-fold diluted inverse aqua regia.