The Role of 3D Printing in the Development of a Catalytic System for the Heterogeneous Fenton Process.

Recycling of catalysts is often performed. Additive manufacturing (AM) received increasing attention in recent years in various fields such as engineering and medicine, among others. More recently, the fabrication of three-dimensional objects used as scaffolds in heterogeneous catalysis has shown innumerable advantages, such as easier handling and waste reduction, both leading to a reduction in times and costs. In this work, the fabrication and use of 3D-printed recyclable polylactic acid (PLA) scaffolds coated with an iron oxide active catalyst for Fenton reactions applied to aromatic model molecules, is presented. These molecules are representative of a wider class of intractable organic compounds, often present in industrial wastewater. The 3D-printed PLA-coated scaffolds were also tested using an industrial wastewater, determining the chemical oxygen demand (COD). The catalyst is characterized using electron microscopy coupled to elemental analysis (SEM/EDX) and thermogravimetry, demonstrating that coating leach is very limited, and it can be easily recovered and reused many times.