Anodic oxidation of pentachlorophenol at Ti/SnO2 electrodes

TLDR: In this article, the electrochemical oxidation of dilute aqueous solutions of pentachlorophenol (PCP) using Ti/SnO2 as an electrocatalytic material has been investigated.

Abstract: The electrochemical oxidation of dilute aqueous solutions of pentachlorophenol (PCP) using Ti/SnO2 as an electrocatalytic material has been investigated The studies were carried out in a two-compartment electrochemical cell at three different current density values (10, 30 and 50 mA cm–2) at 25 °C and using 20 mg L–1 of PCP in 01 M NaOH (pH 10) as supporting electrolyte The PCP concentration and the by-products of the oxidized solution were monitored during the oxidation process using UV and HPLC techniques For the three current densities investigated it was found that the rate of PCP elimination depends only on the specific electrical charge Likewise, the oxidation mechanism was proved to occur through the participation of adsorbed hydroxyl radicals (·OH) formed on the SnO2 surface, whatever the current density used However, as the applied current density was increased, a current efficiency lower than 2% was obtained, which is due to mass transfer limitations In addition, it was observed that the PCP was mineralized to CO2 with conversion percentages as high as 92% and at current density values as low as 10 mA cm–2 The PCP degradation produces two other by-products of oxidation (<10%), namely carboxylic acids, which are non-toxic compounds