Mechanism and kinetics of 2-chlorophenol decomposition using coupled ultrasound and electrocatalysis

• 来源期刊: 中国科学B辑（英文版）
• 年，卷（期）: 2008,（6）
• 页码范围: 577-585
• 页数: 9页
• 语种: 英文
• DOI: 10.1007/s11426-007-0137-2

摘要

A coupled ultrasound/electrocatalysis (US/EC) process was used to enhance the decomposition effi-ciency of organics. The synergetic kinetics and the mechanism of 2-chlorophenol (2-CP) decomposi-tion with coupled US/EC were studied. It was found that in a US/EC process 2-CP is attacked by active radicals (such as hydroxyl radicals) to form 2-chloro-p-benzoquinone, and the latter is oxidized to simple organic acids when the ring is opened. The enhancement factor expressed by the apparent rate constant of 2-CP decomposition with coupled US/EC is 1.324 at a current density of 20 mA.cm-2, an ultrasonic frequency of 20 kHz, an ultrasonic intensity of 0.27 W·cm-2, and a 2-CP initial concentration of 200 mg·L-1, which means that a synergetic effect exists. A model derived from Langmuir adsorption theory of solid surface and reaction kinetics equations can describe exactly the decomposition of 2-CP with coupled US/EC. The numerical values are in good agreement with the experimental data. The model parameters are associated with reaction conditions.