【摘要】 本实验研究了序批式条件下Cr（Ⅵ）和NO₃^-浓度、pH值和H₂含量对于氢自养还原菌同步去除水中Cr（Ⅵ）和NO₃^-的性能及微生物群落的影响.结果表明:系统中存在氢气时,正常活性的氢自养还原菌可实现Cr（Ⅵ）的还原;Cr（Ⅵ）初始浓度不高于2000μg/L时,Cr（Ⅵ）和NO₃^-的还原速率及氢自养还原菌的活性不会受到Cr（Ⅵ）初始浓度的影响;作为一种优先电子受体,NO₃^-会与Cr（Ⅵ）争夺电子,降低Cr（Ⅵ）的还原速率;氢自养还原菌同步还原Cr（Ⅵ）和NO₃^-的最佳pH值为7.0左右,酸性或碱性环境都会抑制Cr（Ⅵ）还原,且NO₂^-会随着pH值的升高逐渐积累;作为电子供体,H₂是还原Cr（Ⅵ）和NO₃^-的必要条件,但H₂足量后,过量提供H₂不能提高Cr（Ⅵ）和NO₃^-的还原速率.更多还原

【Abstract】 The effects on the reduction efficiency and microbial community in simultaneous removal of Cr（Ⅵ）and NO₃^-from water by hydrogen autotrophic reducing bacteria（HARB）using sequential batch experiments was investigated under different Cr（Ⅵ）concentration,NO₃^-concentration,pH value and H₂ content conditions.Results showed that Cr（Ⅵ）can be reduced by active HARB.When the influent concentration of Cr（Ⅵ）was less than 2000μg/L,the reduction rates of Cr（Ⅵ）and NO₃^-,and the activity of HARB was not affected by the initial concentration.As a preferred electron acceptor,NO₃^- competed with Cr（Ⅵ）,causing a decrease in the reduction rate of Cr（Ⅵ）.The optimum pH value for simultaneous reduction of Cr（Ⅵ）and NO₃^- by HARB was about 7.0.Both acidic and alkaline environments can inhibit the reduction of Cr（Ⅵ）.NO₂^-accumulated gradually with the increase of pH value.H₂ as an electron donor was a necessary factor for the reduction of Cr（Ⅵ）and NO₃^-,while excess H₂ did not increase the reduction rate of Cr（Ⅵ）and NO₃^-.更多还原