Extraction-photoacoustic spectroscopic determination of antimony, cadmium, cobalt, nickel, palladium and thallium

Abstract

A photoacoustic spectroscopic method has been developed for the determination of trace amounts of metal ions. It consists in solvent extraction, evaporation of the solvent and photoacoustic measurement on the solid film residue in a gas-microphone cell. Sub-nanogram detection limits have been achieved, together with linear dynamic ranges over 2–3 orders of magnitude, for Cd, Co, Ni, Pd, Sb and Tl using a 17-mW continuous-wave He-Ne laser. The method is sensitive and generally applicable to all species which can be determined in relatively large amounts by conventional extraction-absorption spectrophotometry.