Recent advances in the application of natural iron and clay minerals in heterogeneous electro-Fenton process

Heterogeneous electro-Fenton (EF) using solid catalysts has emerged as a robust advanced oxidation process for wastewater treatment, capitalizing on the advantages of in-situ oxidant generation, minimal iron sludge production, and a wide pH working window. However, synthetic iron-based catalysts face great challenges in practical application due to their high cost and the risk of secondary pollution. In contrast, the use of natural minerals as catalysts has emerged as a promising alternative owing to their cost-effectiveness, abundance, and eco-friendliness natures. Herein, a summary of the application of natural iron and clay minerals in EF is provided, focusing on the performance, catalytic mechanisms, as well as challenges and perspectives for large-scale application.