A Novel Fe.sub.3O.sub.4@C/RM Composite Fabricated from Red Mud and Scrap Tire-Derived Carbon Black: Heterogeneous Activation of Peroxymonosulfate for Oxidative Degradation of Orange II

• Published in: Water, air, and soil pollution air, and soil pollution, 2023-11, Vol.234 (11)
• Main Authors: Wang, Xilin, Sun, Xiaojing, Dai, Ping, Xu, Dongyan
• Format: Article
• Language: English
• Subjects: Air quality management; Diffraction; Hematite; Pyrolysis; Tetracycline; Tetracyclines; X-rays
• ISSN: 0049-6979
• DOI: 10.1007/s11270-023-06690-1

This study focuses on preparation of a novel Fe.sub.3O.sub.4@C/RM composite by carbothermal reduction of red mud (RM) with scrap tire-derived carbon black and its application for the degradation of orange II in water by activating PMS. X-ray diffraction (XRD) measurements revealed that hematite (Fe.sub.2O.sub.3) was reduced to Fe.sub.3O.sub.4 in the pyrolysis process above 600 .sup.oC. The reduction pathway of Fe.sub.2O.sub.3 was inferred by detecting the gas emissions during carbothermal reduction. Morphology analysis indicates that Fe.sub.3O.sub.4 nanoparticles were encapsulated in a carbon matrix, forming a composite with the residual components of RM. The as-prepared Fe.sub.3O.sub.4@C/RM composite exhibited high performance toward orange II degradation with 95.9% removal of orange II within 90 min. Electron paramagnetic resonance (EPR) and quenching tests were applied to illustrate the activation processes of peroxymonosulfate. Both radical and non-radical oxygen species are responsible for the efficient degradation of orange II in the Fe.sub.3O.sub.4@C/RM/PMS system.