甲基叔丁基醚(MTBE)的生物降解特性研究

Biodegradation Characteristics of Methyl Tert-Butyl Ether (MTBE)

采用摇瓶振荡法,利用自行富集驯化培养的混合微生物对甲基叔丁基醚(MTBE)好氧降解规律进行了研究,讨论温度、pH值、MTBE初始浓度、接种量对MTBE降解率的影响。结果表明,以MTBE为碳源的微生物生长极其缓慢,使得MTBE的生物降解性较差,本研究条件下的最高降解率为48.88%,且在约200h的降解时间内没有发现中间产物叔丁醇(TBA)的进一步降解。MTBE降解规律可用Monod-no-growth模型很好描述,其基本降解动力学参数为μmax=0.085h-1,KS=381.70mg·L-1。

In recent years, methyl tea-butyl ether （MTBE） used as gasoline additive has become the second most common contaminant detected in the urban groundwater. Compared with chemical treatment methods such as advanced oxidation technologies （AOTs）, the use of microbes to degrade MTBE is more suitable for the remediation of the contaminated subsurface. In this research, the main factors including temperature, pH, MTBE concentration and inoculation amount of microbes that may affect the biodegradation efficiency of MTBE were studied by using mixed aerobic microbes from enriching and acclimating. The results indicated that the microbes using MTBE as sole source of carbon under aerobic conditions grew slowly with low yields of biomass, which made MTBE difficult to be biodegraded, and the maximum biodegradation efficiency was only 48.88% under the experimental conditions. The degradation byproduct of MTBE, tert-butyl alcohol （TBA） could not be further degraded during 200 h of operating time. In addition, the biodegradation process of MTBE can be well described by monod-no-growth model, with the stimulated results of and being 0.085 h-1 and 381.70 mg.L^-1, respectively.