Effect of silver and copper ions on the decomposition of ozone in water

Features of the kinetics of ozone decomposition in water at pH 2 are studied depending on the concentration of silver and copper ions that are present. The existence of a critical concentration of metal ions (∼3−6 × 10−6 M) is established, below which ions slow the rate of ozone decomposition and above which the accelerate the process. It is concluded that the first region is due to the capture of hydroxyl and other radicals by metal ions, inhibiting the chain of ozone decomposition in water. A further increase in the concentration of ions leads to dominance of their direct interaction with molecules of ozone. A mechanism for the process is proposed and the rate constants of reaction of ozone with silver ions and copper are calculated (0.033 and 0.06 M−1 s−1, respectively).