Studies On Degradation Characteristics And Mechanism Of Decabromodiphenyl Ether By Aerobic Microorganisms

Deca-BDE-degrading bacteria was isolated from E-waste disassembly sites by selective enrichment culture in the experiment condition.The strain was able to grow on Deca-BDE as a sole carbon source and named H.It was identified as Rhodococcus based on its morphological,physio-biochemical identification and 16s rDNA sequence analysis.The optimal condition for degrading Deca-BDE was chosen by orthogonal experiment.Results showed that the optimum conditions were as follows:mass concentration of substate was 50mg/L,temperature was 30℃,pH was 7.0,oscillator speed was 150rpm,reaction time was 7 days,under which the biodegrading rate reached 48.25%.The yeast, toluene, amylum, phenol and Tetrabromobisphenol A were selected as cometabolism substrates.The results showed that yeast, toluene, amylum were more suitable for supporting the cometabolic degradation.However,phenol and Tetrabromobisphenol-A restrained the growth of Strain H.Yeast has the most noticeable supporting effect on degradation,as the biodegrading rate reached 70.88%. IR results showed that hydroxyl, amide group and C-H bond were related to the degradation process.The degradation products was mainly lower brominated diphenyl ethers,such as hexa-,heptabrominated diphenyl ethers.Fe/C electrolysis helped to accelerate debromination process and promote strain H to use Deca-BDE.So degradation rate reached 77.52% with the combination effect of Fe/C and strain H. The degradation products was mainly lower brominated diphenyl ethers,such as hepta-,octa-brominated diphenyl ethers.