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 th...