University of North Florida
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Stuart Chalk, Ph.D.
Department of Chemistry
University of North Florida
Phone: 1-904-620-1938
Fax: 1-904-620-3535
Website: @unf

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Classification: Metal

Citations 3

"Flow Injection Spectrophotometric Determination Of Palladium With DCS-arsenazo"
Anal. Chim. Acta 1992 Volume 256, Issue 1 Pages 113-116
Xing-Cun He*, Ya-Qi Cai, Zhi-De Hu

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.
Palladium Spectrophotometry Heated reaction Interferences

"Continuous Hydride-generation System For The Determination Of Trace Amounts Of Bismuth In Metallurgical Materials By Atomic Absorption Spectrometry Using An Online Stripping-type Generator/gas-liquid Separator"
J. Anal. At. Spectrom. 1997 Volume 12, Issue 6 Pages 637-642

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.
Bismuth Sample preparation Spectrophotometry Phase separator Method comparison Reference material Volatile generation Volatile generation

"Online Concentration And Flow Analysis Of Trace Amounts Of Bismuth With Anion-exchange Method And Ion-exchanger Absorptiometry"
Bunseki Kagaku 1987 Volume 36, Issue 11 Pages 656-661
Yoshimura, K.

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.
Bismuth Ion exchange Spectrophotometry Preconcentration Dowex Resin Sephadex Solid phase detection