DIFFERENTIAL SENSITIVITY OF NH4+ AND NO2− OXIDATION TO CdCl2 AND AlCl3 IN AN AQUEOUS SYSTEM

The effects of different concentrations of CdCl2 and AlCl3 on NH4+ and NO2− oxidation in an aqueous system were investigated. AlCl3 had no effect on NH4+ removal and its oxidation to NO2−, whereas NO2− disappearance was greatly enhanced by AlCl3. In contrast, CdCl2 delayed removal of NH4+ and its subsequent oxidation to NO2− and also decreased the rate of NO2− disappearance. When compared to the controls, NO3− production from NH4+ oxidation decreased severely by CdCl2 whereas slight increase in NO3− production was observed in the presence of AlCl3. The results presented provide evidence for differential sensitivity of NH4+ and NO2− oxidation to AlCl3 and CdCl2 in an aquatic environment.