Ultrasound-Promoted Cold Vapor Generation in the Presence of Formic Acid for Determination of Mercury by Atomic Absorption Spectrometry
- 3 August 2006
- journal article
- research article
- Published by American Chemical Society (ACS) in Analytical Chemistry
- Vol. 78 (17), 6260-6264
- https://doi.org/10.1021/ac0606498
Abstract
A new cold vapor technique within the context of green chemistry is described for determination of mercury in liquid samples following high-intensity ultrasonication. Volatile Hg evolved in a sonoreactor without the use of a chemical reducing agent is carried to a quartz cell kept at room temperature for measurement of the atomic absorption. The mechanism involved lies in the reduction of Hg(II) to Hg(0) by reducing gases formed upon sonication and subsequent volatilization of Hg(0) due to the degassing effect caused by the cavitation phenomenon. Addition of a low molecular weight organic acid such as formic acid favors the process, but vapor generation also occurs from Hg solutions in ultrapure water. The detection limit of Hg was 0.1 μg/L, and the repeatability, expressed as relative standard deviation, was 4.4% (peak height). Addition of small amounts of oxidizing substances such as the permanganate or dichromate anions completely suppressed the formation of Hg(0), which confirms the above mechanism. Effect of other factors such as ultrasound irradiation time, ultrasound amplitude, and the presence of concomitants are also investigated. Some complexing anions such as chloride favored the stabilization of Hg(II) in solution, hence causing an interference effect on the ultrasound-assisted reduction/volatilization process.This publication has 11 references indexed in Scilit:
- Vapor Generation by UV Irradiation for Sample Introduction with Atomic SpectrometryAnalytical Chemistry, 2004
- The Toxicology of Mercury — Current Exposures and Clinical ManifestationsNew England Journal of Medicine, 2003
- Conformational Memory in Photodissociation of Formic AcidJournal of the American Chemical Society, 2002
- Applied SonochemistryPublished by Wiley ,2002
- Room Temperature Sonolysis-Based Advanced Oxidation Process for Degradation of Organomercurials: Application to Determination of Inorganic and Total Mercury in Waters by Flow Injection-Cold Vapor Atomic Absorption SpectrometryAnalytical Chemistry, 2000
- Atomic Absorption SpectrometryPublished by Wiley ,1998
- The use of ozone and associated oxidation processes in drinking water treatmentWater Research, 1998
- The adaptation of the dichromate digestion method for total mercury determination by cold-vapor atomic absorption spectrometry to the analysis of soils, sediments and sludgesAnalytica Chimica Acta, 1994
- Oxidation kinetics of natural organic matter by sonolysis and ozoneWater Research, 1994
- Determination of submicrogram quantities of mercury by atomic absorption spectrophotometryAnalytical Chemistry, 1968