Abstract
Fractional to 5μg of gold, silver and mercury are collected on a sheet (7cm in diameter) of reagent paper impregnated with a few mg of a water-insoluble organic reagent, by a single or repeated filtration of a sample solution (10250ml, acidity 0.10.5N) at the flow rate of about 6ml/min. The recoveries of the metals (after ashing of the paper except for mercury) are usually about 98%. The effects of flow rate, number of filtrations, total quantity of metals, solution volume, acidity and coexisting elements on recovery of the metals are studied. This simple and rapid technique is successfully applied to the separation of low ppm of gold, silver and mercury in copper and lead matrices, the concentration factor of silver with respect to copper being approximately 2×10-3. The reagent paper, which is prepared by treating filter paper with 1% (w/v) dithizone-chloroform or 0.05% (w/v) p-dimethylaminobenzylidenerhodanineacetone solution followed by 0.1N nitric acid, can be stored for over 80 days without any deterioration.
