Optimizing Photocatalytic Efficiency and Durability of Zeolite-Based Catalysts via Cation Doping for Effective Dye Contaminant Removal

Abstract

Ce and Fe decorated on dealuminated zeolite Y (CFDDAZY) framework were prepared using isomorphous substitution method using dealumination treatment and impregnation methods to the formation of Si–O-Ce and Si–O-Fe bonds. For this purpose, we selected three distinct ratios of metals/zeolite, being 1:3, 1:10, and 1:20. An important outcome was achieved with a 1:20 ratio of metals to zeolite, providing strong evidence for the superiority of this configuration. The catalyst was characterized using XRD, FT-IR, UV–Vis, FESEM, TEM, EDX, and BET techniques. The prepared catalyst was evaluated in the degradation of 4-nitrophenol. To optimize the process, we conducted the effect of various parameters, including reaction time, catalyst amount, temperature, pH, isoelectric point, and 4-NP concentration on the photodegradation process. The optimal conditions for the removal of 4-NP were obtained in the presence of DAZY decorated with Fe and Ce under ultraviolet radiation, 40 µL of hydrogen peroxide, 0.03 g of photocatalyst, and a concentration of 5 × 10^–4 M 4-nitrophenol during 90 min. The mineralization of 4-nitrophenol (4-NP) was verified through COD experiments, resulting in a removal efficiency of 72.80%. Studying Hinshelwood’s equations revealed that the reaction rate was pseudo-first-order. The catalyst can be reused up to five times while maintaining its catalytic activity. Furthermore, the proposed degradation mechanism is introduced.