Acta Phys. -Chim. Sin. ›› 2006, Vol. 22 ›› Issue (03): 306-311.doi: 10.1016/S1872-1508(06)60006-5

• ARTICLE • Previous Articles     Next Articles

Electrocatalytic Reductive Dechlorination of 2,4,5-PCB in Aqueous Solution by Palladium-modified Titanium Mesh as Cathode

YANG Bo; YU Gang; HUANG Jun   

  1. Department of Environmental Science and Engineering, Tsinghua University, Beijing 100084, P. R. China
  • Received:2005-08-22 Revised:2005-10-24 Published:2006-03-10
  • Contact: YU Gang

Abstract: Electrocatalytic reductive dechlorination of 2,4,5-PCB(PCB: polychlorinated biphenyls) in aqueous solution containing methanol and hexadecyltrimethyl ammonium bromide (CTAB) was studied in a Teflon-made two-compartment flow-through cell with a palladium-loaded permeable titanium mini mesh cathode and a platinum foil anode. The experiments were carried out to explore the effects of palladium loading, electrode structure, applied cathode potential and catholyte flow rate on dechlorination. The results indicated that the optimal conditions were 3 mg Pd loading /cm2 geometric area, three-layer cathode and -1.10 V (vs SCE) controlled potential. After 9 h electrocatalytic reduction under the optimal conditions, the dechlorination rate of 2,4,5-PCB reached 96.2%, but the conversion rate to biphenyl was 89.6%. The current efficiency changed between 11.3% and 33.0% during the electrocatalytic reduction.

Key words: Palladium-loaded titanium cathode, PCBs, Electrocatalysis, Reductive dechlorination