五氯酚的生物电化学催化厌氧转化过程与机制

Pentachlorophenol Degradation in an Anaerobic System with Bioelectrochemical Catalysis

研究了电催化体系、厌氧微生物体系和厌氧微生物电化学催化体系(电生物体系)对五氯酚(PCP)的降解,研究发现电生物体系的降解效率较电催化体系提高85.2%,较微生物体系提高18.5%.电生物体系中PCP脱氯的途径为:PCP先间位脱氯主要生成2,3,4,6-TeCP和2,4,6-TCP,而后2,4,6-TCP脱氯主要生成2,4-DCP,再经对位脱氯生成邻氯酚和苯酚;苯酚在阳极附近多菌种协同作用下进一步氧化,从而减少苯酚的积累加快了PCP的还原转化.电生物体系通过微生物对电子的"长"距离传递和生物还原转化,形成了电化学与生物的交互反应过程,提高了PCP的降解效果.

The pentachlorophenol （PCP）degradation using an electrocatalytic system, system,and an anaerobic system with bioelectrochemical catalysis （a bioelectrical studied, respectively. The results showed that the degradation efficiency of the an anaerobic system ） was bioelectrical system increased by 85.2% than that of the electrocatalytic system and by 18.5% than that of the microbial system. In the bioelectrical system the main process of the PCP dechlorination was as follow：PCP was dechlorinated at the meta-position and converted to 2,3,4,6-TeCP and 2,4, 6-TCP in turn ,the further dechlorination of 2,4,6-TCP mainly produced 2,4-DCP, and then 2, 4-DCP was dechlorinated at the para-position and generated ortho-chlorophenol and phenol. Phenol oxidation under the multi-strain synergy near the anode reduced the phenol concentration and accelerated the reductive degradation of PCP. Because the bacteria reduced PCP and transferred electrons for a long distance, the electrochemical and biological interactive response proceeded and the efficiency of the PCP degradation improved in the bioelectrical system.