Treatment of aniline by contact biological oxidation on the biofilm
生物膜接触氧化法处理苯胺废水

Biological oxidation of aniline in a contact biological oxidation system, consisting of AN3 bacteria and a small part of nitrifying bacteria, was studied.The degradation products, microorganism population dynamics in the axial direction and influences of pH, concentrations of heavy metal ions on the rate of metabolic transformation of aniline during the development of the biofilm were investigated.The results indicated that the aniline was first degraded to NH+4, then to No-2 or No-3 during biofilm development.The density of nitrifying bacteria near the effluent was hundred times higher than that near the influent.The optimum pH for the metabolism of AN3 bacteria on the biofilm was in the range of 6.9-7.5.Heavy metal ions, especially Hg2+, inhibited the metabolism of the bacteria.