OPTIMIZATION OF A Pd-LOADED COMPOSITE ELECTRODE FOR REDUCTIVE DECHLORINATION OF 2,4-DICHLOROPHENOL IN NEUTRAL AQUEOUS SOLUTION

A Pd-loaded composite electrode was prepared by electrodeposition method, modified by a sodium dodecyl benzene sulfonate (SDBS) doping polypyrrole (PPy) film. Pd particles were uniformly dispersed on a PPy-SDBS film which was previously electrodeposited on the meshed Ti supporting electrode. Preparation parameters of the Pd/PPy-SDBS/Ti electrode were optimized, i.e. SDBS concentration of 1.00 g/L, Pd electrodepositing current of 20 mA, and time of 30 min. The prepared Pd/PPy-SDBS/Ti electrode was characterized by scanning electron microscopy (SEM), cyclic voltammetry (CV) and inductively coupled plasma-atomic emission spectrometry (ICP-AES). Electrocatalytic dechlorination of 2,4-DCP in aqueous solution was performed in a two-compartment cell separated by cation-exchange membrane. The conversion efficiency of 2,4-DCP could be up to 96.7% within 90 min with current of 5 mA when initial concentration was 100 mg/L. The Pd/PPy-SDBS/Ti electrode shows high catalytic activity and low cost, presenting a good application prospect in dechlorination of chlorinated organic compounds.