OXIDATION OF 1,3,5-TRIFLUOROBENZENE AND A LPHA,ALPHA,ALPHA-TRIFLUOROTOLUENE IN AQUEOUS-SOLUTION BY O-3 AND O-3 H2O2/

The mechanisms and kinetics of 1,3,5-trifluorobenzene and alpha,alpha, alpha-trifluorotoluene oxidation by ozone (pH=2) and OH. radicals (gen erated from O-3/H2O2) have been studied. Kinetic experiments show that the reaction rate constants between ozone and these fluoroaromatics a re high (k(O3/trifluorobenzene) = 395+/-90 L mol(-1) s(-1) and k(O3/tr ifluorotoluene) = 90 +/- 21 L mol(-1) s(-1)). Fluoride ion analysis an d GC/MS identification indicate that dehalogenation reactions are invo lved in the oxidation of 1,3,5-trifluorobenzene by O-3 and OH. radical s, whereas the reaction of molecular ozone with alpha,alpha,alpha-trif luorololuene does not yield large amounts of F- ions. Numerous hydroxy lated aromatics have been identified from OH. radical-induced oxidatio n of both 1,3,5-trifluorobenzene and alpha,alpha,alpha-trifluorotoluen e. However, molecular ozone, which also leads to hydroxylated byproduc ts, seems to bring about rapid I,3,5-trifluorobenzene ring opening.