title: Mercury determination by FI-CV-AAS after the degradation of organomercurials with the aid of an ultrasonic field: the important role of the hypochlorite ion.
abstract: Due to new findings, the methodology based on room-temperature ultrasonic irradiation (sonolysis) for conversion of organomercurials into inorganic mercury [J.L. Capelo, I. Lavilla, C. Bendicho, Anal. Chem. 72 (2000) 4979-4984.] is further investigated. Inorganic mercury is selectively determined by Flow Injection-Cold Vapour Atomic Absorption Spectrometry (FI-CV-AAS) using SnCl(2)/HCl. Complete oxidation of methyl-mercury can be accomplished within 90 s whilst phenyl and diphenyl-mercury can be degraded within 10s using a 50% sonication amplitude (100 W nominal power) provided by a probe ultrasonic device (20.5 kHz frequency) and a 1 mol L(-1) HCl liquid medium with the presence of hypochlorite ion. The importance of hypochlorite in reduction of organomercurials by stannous chloride is highlighted. Oxidation kinetics indicated a pseudo first-order reaction for methyl-mercury, phenyl-mercury, and diphenyl-mercury.
authors.affiliation: Requimte, Centro de Química Fina e Biotecnología, Departamento de Química, Faculdade de Ciências e Tecnología, Universidade Nova de Lisboa, Quinta da Torre, Monte de Caparica, Portugal. jlcapelom@dq.fct.unl.pt
authors.forename: J L
authors.initials: JL
authors.lastname: Capelo
authors.forename: G M
authors.initials: GM
authors.lastname: Rivas
authors.forename: L G
authors.initials: LG
authors.lastname: Oliveira
authors.forename: C
authors.initials: C
authors.lastname: Vilhena
authors.forename: A C
authors.initials: AC
authors.lastname: Santos
authors.forename: T
authors.initials: T
authors.lastname: Valada
authors.forename: M
authors.initials: M
authors.lastname: Galesio
authors.forename: P
authors.initials: P
authors.lastname: Oliveira
authors.forename: M D R Gomes da
authors.initials: MD
authors.lastname: Silva
authors.forename: E M
authors.initials: EM
authors.lastname: Gaspar
authors.forename: S
authors.initials: S
authors.lastname: Alves
authors.forename: C
authors.initials: C
authors.lastname: Fernandez
authors.forename: C
authors.initials: C
authors.lastname: Vaz