Alejandra Verónica Devard

BACKGROUND: The development of efficient and stable catalysts for wastewater treatment is limited by metal leaching under reaction conditions. Copper‐based Fenton‐like systems offer advantages over iron catalysts, but their long‐term stability is influenced by synthesis parameters, including the precursor selection, which controls copper dispersion, oxidation states and metal–support interactions. RESULTS: Cu/Al₂O₃ catalysts were synthesized by wet impregnation using oxide, nitrate, sulfate and chloride precursors, calcined at 900 °C and tested in the catalytic wet peroxide oxidation of phenol at 70 °C. All catalysts achieved complete phenol conversion within 30 min, but significant differences in mineralization and copper leaching were observed. Nitrate‐ and sulfate‐derived catalysts (CuAN, CuAS) exhibited smaller crystallite sizes, higher copper dispersion and stronger Cu–support interactions, leading to lower leaching (~35%) and stable activity. Oxide‐ and chloride‐derived catalysts (CuAO, CuACl) showed higher leaching (>40%) but slightly higher total organic carbon removal, attributed to the homogeneous contribution of dissolved copper. X‐ray photoelectron spectroscopy and Auger analyses confirmed variable Cu ⁺ /Cu ²⁺ distributions depending on precursor type, with higher Cu ⁺ content correlating with enhanced redox activity. Total organic carbon conversions ranged from 86% to 89%, and buffered conditions further improved radical stability and mineralization efficiency. Comparative analysis with literature highlighted the competitive performance of CuAN and CuAS catalysts, obtained through a simple impregnation route without dopants. CONCLUSION: Precursor selection is a key parameter for balancing activity and stability of Cu/Al₂O₃ catalysts. Nitrate‐ and sulfate‐derived systems provide improved copper retention without compromising efficiency, offering a scalable strategy for designing sustainable catalysts for advanced wastewater treatment. © 2025 Society of Chemical Industry (SCI).

Microplastic pollution has become a global environmental concern with detrimental effects on ecosystems and human health. Effective removal of microplastics from water sources is crucial to mitigate their impacts. Advanced oxidative processes (AOPs) have emerged as promising strategies for the degradation and elimination of microplastics. This review provides a comprehensive overview of the application of AOPs in the removal of microplastics from water. Various AOPs, such as photocatalysis, ozonation, and Fenton-like processes, have shown significant potential for microplastic degradation. These processes generate highly reactive species, such as hydroxyl radicals, which can break down microplastics into smaller fragments or even mineralize them into harmless byproducts. The efficiency of photocatalytic oxidation depends on several factors, including the choice of photocatalysts, reaction conditions, and the physicochemical properties of microplastics. Furthermore, this review discusses the challenges associated with photocatalytic oxidation, such as the need for optimization of operating parameters and the potential formation of harmful byproducts. Overall, photocatalytic oxidation offers a promising avenue for the removal of microplastics from water, contributing to the preservation of aquatic ecosystems and safeguarding human health. However, further research is needed to address the limitations and optimize the implementation of this process for effective and sustainable microplastic remediation.