Abstract: The palladium sample was injected into a carrier stream of water which was merged with streams of 0.5 M H2SO4 and 0.03% 2-(2-arsenophenylazo)-7-(2,6-dichloro-4-sulfophenylazo)-1,8-dihydroxynaphthalene-3,6-disulfonic acid (I). The reaction proceeded in a 100 cm x 0.7 mm coil heated at 80°C and the absorbance was measured at 635 nm (ε 17,000). The molar ratio of Pd to I in the complex was 1:2. The calibration graph was rectilinear in the range 0 to 8.0 µg mL-1 of Pd and the detection limit was 0.05 µg mL-1. The sample throughput was 90 h-1 with 100 µL injections. In the determination of 6 µg mL-1 of Pd, the coefficient of variation of peak height was 0.57% (n = 10). I was selective in the presence of precious metals, and was used for the analysis of metallurgical samples. A flow injection spectrophotometric method for the determination of palladium involves the measurement of the absorbance of the 1:2 palladium:DCS-arsenazo complex at 635 nm (molar absorptivity 1.7 x 104 L mol-1 cm-1). The calibration graph is linear over the range 0-8.0 µg mL-1. The detection limit is 0.05 µg mL-1. The sample throughput is 90 h-1 with 100 µL sample injections. The proposed method has been applied to the determination of palladium in metallurgical samples without preliminary separation.

Abstract: Sample-solution (1 M HCl medium) preparation procedures are presented for Sn alloys, steel, bronze and brass. A diagram of the flow injection manifold is presented; the sample solution and 1% NaBH4 solution (both 50 µL) are injected simultaneously into streams (both 1.9 ml/min) of water and 1 M HCl, respectively, which subsequently merge (cf. Bergamin et al., Anal. Chim. Acta, 1978, 101, 17) before passage through a 15 cm reaction coil a nd then through a stripping-type gas-liquid reactor-separator (made of acrylic; diagram presented). The generated BiH3 is carried in a stream of N2 to a quartz atomization furnace maintained at 900°C for absorbance measurement at 223.1 nm. The calibration graph is linear up to 100 ng/ml of Bi, and the detection limit is 320 pg/ml. The RSD (n = 20) at 100 ng/ml was 1.9%, and the results for standard reference materials and other alloy samples agreed with the certified values and results obtained by ETAAS, respectively.

Abstract: Bismuth (0.012 to 0.5 nmol) in various samples (e.g., 1 l of water) was pre-concentrated as a chloro-complex from 0.1 to 0.6 M Cl- by using a Dowex 1-X8 anion-exchange column (Cl- form; 100 to 200 mesh). Bismuth was desorbed with 0.15 M H2SO4 at a flow rate of 1.2 mL min-1 and mixed with a solution containing 1 M KI at 0.3 mL min-1. After introduction into the flow-through cell, the light path portion of which was filled with QAE Sephadex A-25 anion exchanger, the light attenuation due to the iodo-complexes of Bi (concentrated on the anion exchanger in the cell) was measured directly at 472 nm, with high precision. The calibration graph for Bi was rectilinear and the method was applied to samples of rocks and metals.