A solid composite electrode for the determination of the electrochemical oxygen demand of aqueous samples.

A composite electrode containing graphite, paraffin, AgO and CuO is described for the determination of the electrochemical oxygen demand (EOD) of waste waters. The oxidation of dissolved organic compounds at the electrode is based on a heterogeneous chemical reaction of AgO/CuO with the organic constituents of the waste water. This chemical reaction can be followed by a solid state electrochemical oxidation of the formed Ag(2)O/Cu(2)O. The method has been tested with various organic compounds and applied to real samples of sewage water. The EOD values correlate well to BOD and COD values.