三氯乙烯在苯酚菌中的共代谢降解性能研究

Co-metabolic biodegradation of trichloroethylene by acclimated phenol degrading bacteria

通过生物降解实验考察三氯乙烯(TCE)在苯酚驯化微生物中的共代谢降解性能,并进行动力学分析。结果表明,苯酚是TCE-苯酚共代谢过程必不可少的共代谢基质;TCE的共代谢降解与苯酚和TCE初始浓度有关。TCE在降解初期会出现一个短暂的迟滞期,TCE的大量降解要在苯酚被利用后才发生;高质量浓度TCE(>9mg/L)对共代谢降解有抑制作用。苯酚/TCE(质量比)在10～15以上时,苯酚菌对TCE的去除率较大。Haldane模型能够很好地拟合苯酚和TCE的比降解速率。动力学分析表明,微生物对苯酚的亲和力要大于TCE,苯酚对TCE共降解具有竞争性抑制作用,TCE对微生物存在毒性抑制作用;结果证实了生物降解实验的结论。

The batch experiments were carried out to investigate the co-metabolic degradation of trichloroethyl- ene （TCE） by acclimated phenol degrading bacteria. The results showed that phenol was an essential co-substrate the TCE degradation rate was dependent on the initial concentrations of phenol and TCE in co-metabolic degradation system. Active biodegradation of TCE followed after a short lag phase for building up a critical density of acclimated phenol degrading bacteria. A high initial TCE concentration of 〉9 mg/L inhibited its degradation an initial phenol/TCE ratio of 〉10-15 enhanced the final removal of TCE. The degradation curves of phenol and TCE were well represented by the Haldane inhibition model. The mixed culture bacteria had a higher affinity for phenol than TCE; phenol had competitive inhibition effect on TCE degradation ; the inhibition effect of TCE to bacteria was observed in the high initial concentration runs.