Persulfate-enhanced Photocatalytic Degradation of Methylene Blue

Abstract

Abstract. Based on the new advanced oxidation technology activated by sulfate radicals, this work established a promising method on degradation of Methylene Blue (MB). Different effects of operating parameters such as the threshold concentration of sodium persulfate(SPS), initial pH value, coexisting ions and ultraviolet(UV) intensity, were studied in aim to obtain an optimal condition of MB degradation. Results showed that the increase of SPS concentration and UV intensity, as well as the decrease of initial pH value could significantly enhance MB degradation rate, but coexisting ions did greatly inhibit efficiency to an extent which was closely dependent upon the ion content. When the concentration of SPS was 0.5mM and the initial pH value is 3 under the irradiation of a 5W UV light, the degradation rate of MB reached the maximum value of 95% after an hour. Furthermore, Total Organic Carbon (TOC) of the MB system decreased from the initial 92.4 mg/L to 7.24mg/L.