Sustainable removal of antipyrine from wastewater via an Eco-Friendly heterogeneous Electro-Fenton-like process employing Zero-Valent iron nanoparticles loaded activated carbon

Abstract

This study addresses the growing environmental and health concern associated with pharmaceutical compounds detected in wastewater by employing an innovative and environmentally friendly approach. Polyphenol reducing agents were extracted from palm petiole (PP) using a coffee marker to synthesize zero-valent iron nanoparticles (P-NZVI) in an environmentally sustainable manner. The residual PP materials after extraction were used to prepare an eco-friendly activated carbon (AC). Subsequently, the syntetized P-NZVIwere integrated with AC to form a composite AC-NZVI. After the physical–chemical characterization of the developed materials, AC and AC-NZVI were evaluated as catalysts in a heterogeneous electro-Fenton-like (EFL) process, employing a boron-doped diamond (BDD) as anode and carbon-felt (CF) as cathode to enhance antipyrine (ATP) degradation. This study investigates influential factors such as catalyst dosage, pH, current density, scavengers’ presence and water matrices effect. Results showcase a remarkable 97 % ATP removal efficiency and low energy consumption (EC) of 0.0683 kWh/g over 60 min EFL in deionized water with 1.4 g/L AC-NZVI and at current density of 10 mA/cm2. Quenching experiments emphasize hydroxyl radicals as the predominant species, particularly in acidic conditions. Notably, AC-NZVI exhibits high removal efficiencies even in real wastewater, achieving 87 % ATP removal. The study confirms the recyclability and stability of the AC-NZVI catalyst over five cycles, confirmed by comprehensive analyses, including FTIR, XPS, Raman, and XRD, achieving a mineralization efficiency of 84 % within 3 h. Elucidation of the ATP degradation pathway is accomplished through LC-MS.