Electrochemical reductive dechlorination of chlororganic compounds on carbon cloth and metal-modified carbon cloth cathodes

Electrochemical reductive dehalogenation of chlorinated organic compounds in organic and aqueous solutions was studied. An electrolytic cell, separated into two compartments by placing a cation or anion exchange membrane between the cathode (carbon cloth and metal-modified carbon cloth) and the anode (Pt net), was used. Chlorinated aromatic compounds were dechlorinated in non-polar organic solvents with a cathode made of carbon cloth (industrially produced, cheap, stable in different solvents, with good adsorption properties). In concentrated solutions current efficiencies in DMSO and MeCN up to 75% were achieved, decreasing to 20% in diluted solutions. Complete electrocatalytic reductive dechlorination of chlorinated aromatic compounds was achieved in MeOH on the carbon cloth modified by Pd. Among metal cathodes, only on Pb was it possible to carry out a complete dechlorination in MeOH, but Pb corroded during the reaction. Chlorinated aliphatic compounds were decomposed to non-chlorinated products even in an aqueous solution by using electrochemical dehalogenation on the Zn-modified carbon cloth cathode. Carbon cloth seems to be the most suitable cathode material for electrochemical reductive dechlorination of chlorinated organic compounds with a good yield and current efficiency.