In situ formation of supported metallic iron on red ceramic waste and its reactivity

The in situ formation of metals has grown in recent years with the aim of applying the obtained metals in various fields of knowledge, ranging from catalysis to healthcare, by obtaining materials capable of replacing implants such as platinum or titanium. Part of this pursuit requires understanding and obtaining metals in general. The metallic iron in question has been relatively less obtained, and its application is promising and cost-effective due to the involved metal. In this study, we demonstrate the synthesis of metallic iron supported on red ceramic waste (RCW) and its reactivity in an atmosphere containing sulfur. The objective of this research is to showcase the synthesis of metallic iron associated with an unconventional support (waste) and its application in reacting with a sulfur-containing gas atmosphere. This was achieved through particles synthesized using the hydrothermal method, and the measurements were conducted through in situ X-ray absorption spectroscopy with temporal resolution in the XANES region at the Brazilian Synchrotron Light Laboratory (LNLS). In situ DXAS measurements allowed the monitoring of the reactivity of the corresponding metallic iron particles during activation and sulfidation processes. The obtained results demonstrated satisfactory metallic formation, effective adhesion of the support, and successfully achieved reactivity. • Use of red ceramic waste as a sustainable support for Fe particles. • Complete conversion from Fe⁺³ to Fe⁰ occurs below 600 °C using H₂. • DXAS reveals efficient reduction and nanoscale structure of Fe particles. • XANES analysis shows sulfur adsorption and absence of Fe sintering.