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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 N2 adsorption–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 (R2 > 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. [ABSTRACT FROM AUTHOR]

• The bifunctional Fe-ZSM-5 nano-adsorbent removed Metformin by adsorption. • The nano-adsorbent had the high surface area and uniform morphology. • Langmuir adsorption capacity was 14.992 mg g−1 at T = 25 °C. • The data well fitted the Langmuir isotherm model (R2 = 0.999). • The developed nano-adsorbent had high reusability. Metformin (MET) is one of the anti-diabetic drugs which is widely used in the world and found abundantly in pharmaceutical wastewater. The purpose of this study, the adsorption of MET from aqueous solution by Fe-ZSM-5 (Fe-Z) zeolite as an adsorbent. The zeolite characterization was analyzed using FTIR, FE-SEM, TEM, XRD, and N 2 adsorption-desorption Techniques. The adsorption was performed in a batch system, and the effect of parameters such as solution pH, initial concentration of MET, adsorbent dose, temperature, and contact time was investigated to optimize the adsorption process. Adsorption isotherms were studied by Langmuir, Freundlich, Temkin and Dubinin-Radushkevich models. The Langmuir model with a high correlation coefficient (R2 = 0.999) and the maximum monolayer adsorption capacity (q max = 14.992 mg g−1) at T = 25 °C showed the highest consistent with MET adsorption on the Fe-Z zeolite. The kinetic data were best represented by the pseudo-second-order model. Also, thermodynamic parameters such as enthalpy changes (ΔH), Gibbs energy changes (ΔG), and entropy changes (ΔS) were investigated. The highest adsorption efficiency was 95.7% at the optimum operating conditions: pH = 8.33, t = 25 °C, 1.1 g L−1 Fe-Z and C 0 = 10 mg L−1. The developed nano-adsorbent had high reusability including only 4.4% drop in the removal efficiency. The results showed that the Fe-Z zeolite could be a promising adsorbent for the MET removal. [ABSTRACT FROM AUTHOR]