Kinetics and mechanism of oxidation of tetrachloroethylene with permanganate

摘要: Abstract The kinetics, reaction pathways and product distribution of oxidation tetrachloroethylene (PCE) by potassium permanganate (KMnO4) were studied in phosphate-buffered solutions under constant pH, isothermal, completely mixed zero headspace conditions. Experimental results indicate that the is first-order with respect to both PCE KMnO4 has an activation energy 9.3±0.9 kcal / mol . second-order rate at 20 °C 0.035±0.004 M −1 s , independent pH ionic strength (I) over a range 3–10 I∼0–0.2 M, respectively. PCE–KMnO4 may proceed through further and/or hydrolysis pathways, greatly influenced acidity solution, yield CO2(g), oxalic acid, formic acid glycolic acid. Under acidic conditions (e.g., 3), pathway will dominate tends be directly mineralized into CO2 chloride. neutral 7) alkaline 10), hydroxylation dominates primarily transformed prior complete mineralization. Moreover, all chlorine atoms are rapidly liberated during chloride production very close degradation.