Iron ore tailings as catalysts for oxidation of the drug paracetamol and dyes by heterogeneous Fenton

• Published in: Journal of environmental chemical engineering Vol. 6; no. 5; pp. 6545 - 6553
• Main Authors: Augusto, Thiago de Melo, Chagas, Poliane, Sangiorge, Daniel Lara, Mac Leod, Tatiana Cristina de Oliveira, Oliveira, Luiz C.A., Castro, Cínthia Soares de
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01-10-2018
• Subjects: Heterogeneous Fenton; Iron ore tailings; Oxidation; Paracetamol; PET residue; PET residue; Paracetamol; Oxidation; Heterogeneous Fenton; Iron ore tailings
• ISSN: 2213-3437; 2213-3437
• DOI: 10.1016/j.jece.2018.09.052

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•New composite material based on iron ore tailings (R) - PET bottles residue.•R thermal reduction with CH4: increased activity for drug and dye oxidation.•The enhanced activity of R-PET and R-CH4 is related to Fe2+ species formation.•Contaminants removal mechanism from water by R-PET: adsorption and Fenton oxidation.•R-CH4 highly active and reusable catalyst for oxidation of organic contaminants.
An iron mining residue was used as generated (R) or modified to produce heterogeneous catalysts for the Fenton reaction. The residue (R) was thermally treated at 600 °C under reducing atmosphere of CH4 (R-CH4) or impregnated with polyethylene terephthalate (PET) powder waste (from bottle recycling) and treated under inert N2 atmosphere at 600 °C to produce a R-PET composite. The R is mainly composed of SiO2, hematite (α-Fe2O3) and goethite (FeOOH) whereas the R-CH4 present a reduced iron phase of wustite (FeO). The R-PET is composed of carbon islands (≈10 wt.% of carbon content) dispersed over the oxides matrix. A partial iron reduction (Fe3+ → Fe2+) occurred during the thermal decomposition of PET thus forming magnetite (Fe3O4). Catalytic tests for H2O2 decomposition showed that the modified catalysts (R-CH4 and R-PET) presented increased activity compared to pure R, possibly due to the presence of reduced iron phases, and the reaction follows a radical mechanism. The catalysts were very active for dye oxidation (methylene blue and rhodamine B) through heterogeneous Fenton and the emergent contaminant, the paracetamol drug, especially R-CH4 (MB removal > 62%, RhB and PRC > 90%). The catalysts (mainly the R-CH4) can be recovered and reused for at least 5 reaction cycles.