Determination of platinum and palladium in strongly acid solution by means of flow injection analysis

Microamounts of Pt(II/IV) (0.25–800 μg/ml) and Pd(II) (5–600 μg/ml) in> 0.5 M hydrochloric acid can readily be determined by means of a simple FIA method based on the selective reaction of tin(II)chloride with these metals. The FIA method has a high linear dynamic range, and is relatively free from interferences of many transition metals, with the exception of Au and Rh; small amounts of other PGMs can be tolerated. Determination of Pt on a hydrogenation catalyst by this method compares well with that found by flame atomic absorption spectroscopy. By monitoring at two or more wavelengths, Pt and Pd can be determined in mixtures by this means, to yield a simple, cost-effective FIA method for possible on-line determinations and quality control of, in particular, Pt containing acidic refinery and other process streams.