Preparation of FeO/C Composite Material from Red Mud for the Degradation of Acid Orange 7.

This study presents a novel FeO/C composite material synthesized from red mud through a process of magnetic roasting and separation. The research explores the impact of FeO/C dosages, sodium persulfate (PS) concentrations, and initial solution pH on the chemical oxygen demand (COD) removal efficiency using Acid Orange 7 as a model pollutant. Optimal conditions were identified as 3 g/L FeO/C, 20 mM PS, and an initial pH of 2, achieving a 94.11% COD removal efficiency within 30 min. X-ray diffraction and photoelectron spectroscopy analyses confirmed that the magnetization roasting process effectively transformed red mud's ferric oxide (FeO) into magnetite (FeO). Concurrently, FeO interacted with residual carbon to form the FeO/C composite. This composite demonstrated superior catalytic performance, along with excellent recyclability and reusability.