2,4,6-trichlorophenol (2,4,6-TCP), as the probe pollutant, was treated by advanced oxidation technology of zero-valent iron/potassium persulfate(Fe0/PS)enhanced by ultrasound. The effects of the initial concentration, pH value, concentration of PS and the dosage of Fe0 on the degradation were studied. Based on the comparison of the reaction rate, the concentration change of ferrous ions among the different system and the identification of the types of free radicals, the preliminary degradation mechanism of the system was also explored. The results showed that the 2,4,6-TCP removal efficiency could up to 95.5% under the conditions of initial concentration of 20mg/L, Fe0 dosage of 0.2g/L, pH value of 6and PS concentration of 0.4g/L. The first 20min reaction followed the first-order reaction kinetics equation. The sulfate radical and hydroxyl radical both existed in the combined system and the sulfate radicals play a major role in the degradation of 2,4,6-TCP. The ultrasound could significant accelerate the degradation of pollutants by accelerating the renewal of the surface of iron powder to produce more ferrous ions.
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