Iron modified zeolite carrier for efficiently pharmaceutical pollutant degradation in heterogeneous electro-Fenton: Influence factors and kinetic

摘要

In this study, the high silica ZSM-5 carrier was modified with the iron species and applied as a heterogeneous electro-Fenton (EF) catalyst for pharmaceutical pollutant degradation. The carrier was prepared by the hydrothermal method and followed by impregnation. The physicochemical properties were evaluated by field emission scanning electron microscopes (FE-SEM), FT-IR, X-Ray diffraction (XRD), and N_2 adsorp-tion-desorption techniques. The impregnated carrier had high crystallinity, high specific surface area, and uniform dispersion of iron species. The effect of different operating conditions was studied on the phenazopyridine (PHP) degradation efficiency. The optimal efficiency of PHP degradation (ca. 92.5%) was obtained at pH of 3.0, the current density of 100 mA, catalyst loading of 0.2 g L~(-1) and T = 25°C. The data of kinetic showed that the degradation of PHP followed Pseudo-First-Order kinetic, including the high accuracy (R~2 ＞ 0.95). The developed catalyst had the high stability and reusability for the PHP degradation in the EF process, while the degradation efficiency dropped only 0.5% for the regenerated catalyst.