Degradation of 2,4-Dichlorophenol by Nitrilotriacetic acid-modified photo-Fenton system: effects of organic and inorganic factors

Abstract

ABSTRACT It has proved that the photo-Fenton system modified by polycarboxylic acid is effective against the degradation of organic pollutants. Still, its effect and impact on actual water bodies are not clear. Therefore, this study mainly discussed the effect of actual water elements on the degradation of 2,4-Dichlorophenol in photo-Fenton system modified by Nitrilotriacetic acid (NTA) and its mechanism in pure water. The specific research contents were: the effect of initial concentration of 2,4-Dichlorophenol on its degradation efficiency; the effect of organic matters on the degradation of 2,4-Dichlorophenol; the effect of cations and anions; the effect of different actual water bodies. And the main results were as follows: In the effect of initial concentration, when the concentration of 2,4-Dichlorophenol was 20 mg·L−1, the degradation efficiency was the best (reached 100%). But, with the increase of initial concentration, the degradation efficiency of the system became worse and worse; the coexistence of the same kind of organic compounds can inhibit each other’s degradation, and the degradation rate of pollutants in the mixed system was slower than that in the single system; the addition of anions and cations inhibited the degradation of 2,4-Dichlorophenol, and the degradation efficiency varied with the concentration of ions, in which the effect of anions was more complex; the degradation efficiency of 2,4-Dichlorophenol in three kinds of actual water bodies was lower than in deionized water, especially in PPMW. However, the degradation rates of DSTP and NLW were the fastest in the first 20 min.