Anodic destruction of 4-chlorophenol solution

The electrochemical oxidation of 4-chlorophenol solutions was studied using a dimensional stable anode (DSA), made of pure titanium sheet mesh coated with Ti/TiO2 and RuO2 film. An electrochemical cell with one working electrode and two counter-electrodes was designed. A gas collecting system to collect the electrolysis gaseous products was also designed. The influence of current density (6.51-21.58 mA/cm(2)), pH (2.0-12.6) and initial 4-chlorophenol concentration (25-100 mg/l) on the destruction was investigated. Complete elimination was successfully achieved within 2 h for most investigated conditions. Highest rates of elimination were achieved at a pH of 12.6. A new approach to calculate the current efficiency (CE) of the cell was proposed. The volumes of the gases produced at the anode and at the cathode were the basis for the new CE calculations. It was observed that the worst CE was approximately 20% and the best CE was approximately 89%. The most efficient pH was at 12.6 and the most efficient current density was at 11.39 mA/cm(2). (C) 2000 Elsevier Science B.V. All rights reserved.