The pathway of the ozonation of 2,4,6-trichlorophenol in aqueous solution
臭氧氧化水中2,4,6-三氯酚的反应机理研究

The reaction mechanism and pathway of the ozonation of 2,4,6-trichlorophenol (2,4,6-TCP) in aqueous solution were investigated. The removal efficiency and the variation of H2O2, Cl-, formic acid and oxalic acid were studied during the ozonation process. The results showed that when there was no scavenger, the removal efficiency of 0.1mmol?L-1 2,4,6-TCP could reach 99% within 6 min by adding 24mg?L-1 ozone. The reaction of molecular ozone with 2,4,6 TCP resulted in the formation of H2O2. The maximal concentration of H2O2 detected during the ozonation could reach 22.5% of the original concentration of 2,4,6-TCP. The reaction of ozone with H2O2 resulted in generating a lot of OH? radicals. Therefore, 2,4,6-TCP was destroyed to formic acid and oxalic acid by ozone and OH? radicals together. With the inhibition of OH? radicals, ozone molecule firstly destroyed 2,4,6-TCP to form chlorinated quinone, which was subsequently oxidized to formic acid and oxalic acid. Two reaction pathways of the degradation of 2,4,6-TCP by ozone and O3/OH? are proposed.