Ligninsulfonate ozonation in the presence of transition metal ions

The kinetics of ozone reactions. with aqueous solutions of ligninsulfonate (LS) in the presence of transition metal ions Fe2+, Mn2+, Co2+ has been investigated. Metal ions are found to influence the rate and pathways of ozone reaction with LS. The acceleration of the reaction in the presence of Fe2+ is the most significant. The mechanism of these processes is discussed. The formation of Me2+ complex with LS functional groups is shown. Me2+ oxidation in [LS...Me2+] complex is indicated to be the limit stage of the reaction. Metal ions addition to LS solutions is proved to cause slowing down of LS aromatic rings destruction by ozone.