Self-regeneration of activated carbon modified with palladium catalyst for electrochemical dechlorination

Catalyst regeneration and the retention of high catalytic activity are still the critical issues in environmental application. A novel fluidized gas–liquid–solid electrochemical reactor was developed to simultaneously remove chlorinated pollutants and in situ regenerate the spent catalyst. Activated carbon modified with palladium catalyst (AC–Pd) was prepared for electrochemical dechlorination. For the 4-chlorophenol wastewater of initial concentration 200 mg L−1, the removal efficiency could nearly reach 100% in less than 30 min. Catalytic activity of AC–Pd catalyst was preserved effectively even in consecutive cycling run without special regeneration. OH radicals, generated by electrochemical reaction, played a critical role in self-regeneration of AC–Pd. High catalytic activity of spent AC–Pd catalyst provided an attractive alternative in wastewater treatment.