Biofilm-electrode process with high efficiency for degradation of 2,4-dichlorophenol

• Published in: Environmental chemistry letters 2011-09, Vol.9 (3), p.383-388
• Main Authors: Zhang, Xue-Na, Huang, Wei-Min, Wang, Xuan, Li, Huiting, Lu, Hai-Yan, Lin, Hai-Bo
• Format: Article
• Language: English
• Subjects: 2,4-dichlorophenol; Analytical Chemistry; Aromatic compounds; bacteria; Biodegradation; Biofilms; Chemical industry; Chemical industry wastewaters; Chemical oxygen demand; Dechlorination; Earth and Environmental Science; Ecotoxicology; Electrochemistry; Electrodes; Environment; Environmental Chemistry; Geochemistry; Industrial wastewater; Original Paper; oxidation; Pollution; wastewater; Water pollution; Water treatment
• ISSN: 1610-3653; 1610-3661
• DOI: 10.1007/s10311-010-0290-2

2,4-Dichlorophenol (2,4-DCP) from chemical industry wastewaters has caused serious environmental pollution. Removal of 2,4-DCP using either physico-chemical or biological methods is not very efficient. In this paper, a combination of biological and electrochemical methods gave satisfactory results. By comparisons of the degradation of 2,4-DCP and the removal of chemical oxygen demand (COD) in electrochemical, biological and biofilm-electrode processes, it was found that the biofilm-electrode process possesses the highest degradation efficiency and removal rate; both the pure electrochemical and the pure biological processes were far less efficient. The removal efficiency of 2,4-DCP using the biofilm-electrode process was 100% in 48 h, while that using the pure electrochemical and the pure biological processes were 62 and 42%, respectively. The experiments show that the current of 5 mA for the cathode of 9 cm2 and the initial concentration 100 mg/l of 2,4-DCP were the optimal parameters of technology for the biofilm-electrode process. The excellent effects are due to the withdrawing electron action of bacterium, electrochemically anodic oxidation and cathodic dechlorination. It is the first time that the biofilm-electrode method was applied in 2,4-DCP degradation. Here, we demonstrated that biofilm-electrode process is a promising method to remove some aromatic compounds in industrial wastewater.