Polybrominated diphenyl ethers （PBDEs） have been widely used as fire-retardants. Due to their high production volume, widespread usage, and environmental persistence, PBDEs have become ubiquitous contaminants in var...Polybrominated diphenyl ethers （PBDEs） have been widely used as fire-retardants. Due to their high production volume, widespread usage, and environmental persistence, PBDEs have become ubiquitous contaminants in various environments.Nanoscale zero-valent iron （ZVI） is an effective reductant for many halogenated organic compounds. To enhance the degradation efficiency, ZVI/ Palladium bimetallic nanoparticles （nZVI/Pd） were synthe- sized in this study to degrade decabromodiphenyl ether （BDE209） in water. Approximately 90% of BDE209 was rapidly removed by nZVI/Pd within 80 min, whereas about 25% of BDE209 was removed by nZVL Degradation of BDE209 by nZVI/Pd fits pseudo-first-order kinetics. An increase in pH led to sharply decrease the rate of BDE209 degradation. The degradation rate constant in the treatment with initial pH at 9.0 was more than 6.8 x higher than that under pH 5.0. The degradation intermediates of BDE209 by nZVI/Pd were identified and the degradation pathways were hypothesized. Results from this study suggest that nZV//Pd may be an effective tool for treating polybromi- nated diphenyl ethers （PBDEs） in water.展开更多
文摘Polybrominated diphenyl ethers （PBDEs） have been widely used as fire-retardants. Due to their high production volume, widespread usage, and environmental persistence, PBDEs have become ubiquitous contaminants in various environments.Nanoscale zero-valent iron （ZVI） is an effective reductant for many halogenated organic compounds. To enhance the degradation efficiency, ZVI/ Palladium bimetallic nanoparticles （nZVI/Pd） were synthe- sized in this study to degrade decabromodiphenyl ether （BDE209） in water. Approximately 90% of BDE209 was rapidly removed by nZVI/Pd within 80 min, whereas about 25% of BDE209 was removed by nZVL Degradation of BDE209 by nZVI/Pd fits pseudo-first-order kinetics. An increase in pH led to sharply decrease the rate of BDE209 degradation. The degradation rate constant in the treatment with initial pH at 9.0 was more than 6.8 x higher than that under pH 5.0. The degradation intermediates of BDE209 by nZVI/Pd were identified and the degradation pathways were hypothesized. Results from this study suggest that nZV//Pd may be an effective tool for treating polybromi- nated diphenyl ethers （PBDEs） in water.
