Vol 64 No 4 (2019): Journal of the Chilean Chemical Society
Original Research Papers


Sebastián Pizarro
Instituto de Investigación Multidisciplinario en Ciencias y Tecnologías, Universidad de La Serena, Casilla 599, Benavente 980; La Serena, Chile
Michael Araya
Centro de Investigación y desarrollo tecnológico en Algas (CIDTA), Facultad de Ciencias del Mar, Universidad Católica del Norte, Larrondo 1281, Coquimbo, Chile
Francisco Gajardo
Departamento de Química, Facultad de Ciencias, Universidad de La Serena, Casilla 599, Benavente 980; La Serena, Chile.
Darly Concha
Departamento de Química, Facultad de Ciencias, Universidad de La Serena, Casilla 599, Benavente 980; La Serena, Chile.
Alvaro Delgadillo
Departamento de Química, Facultad de Ciencias, Universidad de La Serena, Casilla 599, Benavente 980; La Serena, Chile.
Published December 16, 2019
  • cobaloxime,
  • cyclic voltammetry,
  • organochlorines,
  • catalysis


In this work the electrochemical degradation of polychlorinated compounds using Co(dmgH)2Cl(py), Co(dpgH)2Cl(py), Co(chgH)2Cl(py) and Co(dbegH)2Cl(py) (where dmgH is dimethylglyoximato, dpgH is diphenylglyoximato, chgH is 1,2-cyclohexanedionedioximato and dbegH is di(4-methylbenzoate)glyoximato) is described. The degradation was studied using cyclic voltammetry by monitoring current changes in the zone near to the Co(II/I) half wave potential as the concentration of the organochloride in the electrochemical cell is increased. Hexachloroethane (HCA) was used as organohalide substrate, while gamma-hexachlorocyclohexane (lindane), 1,2-dichloroethane, and 1,1,1-trichloroethane were used for comparative studies.  The major dechlorination product of HCA, detected through head space GC-MS experiments after bulk electrolysis, was tetrachlorethylene. The rate constants of the dechlorination processes were estimated using the foot-of-the-wave analysis (FOWA), the values obtained were 1.10×105, 2.59×104, 4.91×10 and 1.83×104 for Co(dmgH)2Cl(py), Co(dpgH)2Cl(py), Co(chgH)2Cl(py)  and Co(dpegH)2Cl(py) respectively.




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