Résumé
Olive mill wastewater (OMW) contains high concentrations of organic substances that pose significant environmental threats to aquatic and terrestrial ecosystems. This study developed an effective photocatalytic treatment method to decolorize and remove phenolic compounds form OMW. Copper vanadate nanoparticles (Cu3V2O8 and β-Cu2V2O7) were synthesized using a robust coprecipitation method and explored for the first time as mixed-oxide photocatalysts for the treatment of OMW. The nanoparticles were characterized using XRD, FTIR-ATR, SEM/EDS, N₂ adsorption-desorption, ICP-OES, XPS, and DRS. The analysis revealed band gaps of 1.81 eV for Cu3V2O8 and 2.38 eV for β-Cu2V2O7. Photocatalytic degradation was assessed under natural sunlight across various pH levels. Cu3V2O8 achieved superior performance by removing 99.52 ± 0.3 % of total phenolic compounds within 180 min, ranking it among the best catalysts and methods previously reported. The photocatalysts further demonstrated significant stability, maintaining activity after four reuse cycles with real OMW (1:100 dilution). The synthesis of both phases of copper‑vanadium mixed oxides presents a promising strategy for OMW treatment that can be further explored on larger scale.