Mesoporous Fe-doped MgO nanoparticles as a heterogeneous photo-Fenton-like catalyst for degradation of salicylic acid in wastewater. Issue 4 (August 2021)

• Record Type: Journal Article
• Authors: Silva, Manoj; Baltrus, John; Williams, Clinton; Knopf, Allan; Zhang, Lihua; Baltrusaitis, Jonas
• Is Part Of: Journal of environmental chemical engineering. Volume 9:Issue 4(2021)
• Publication Date: 2021-08
• Subjects: Heterogeneous photo-Fenton -- Catalysis -- MgO nanoparticles -- Wastewater treatment -- Mesoporous catalysts; Chemical engineering -- Environmental aspects -- Periodicals; Environmental engineering -- Periodicals; Chemical engineering -- Environmental aspects; Environmental engineering; Periodicals; 660.0286
• DOI: 10.1016/j.jece.2021.105589
• Languages: English
• ISSNs: 2213-2929

Abstract

Abstract: Mesoporous Fe-doped MgO nanoparticles were synthesized using a facile sol-gel method and utilized for photo-Fenton-like degradation of salicylic acid (SA). The MgO surface dissolution facilitated an increase in the pH under the reaction conditions that allowed the Fe-MgO catalyst to be active without detectable iron leaching. Under simulated solar radiation, SA was completely degraded with an initial rate constant of 0.048 min −1 at the optimal reaction conditions of 500 ppm loading of 5% Fe-MgO, 20 mM H2 O2 concentration, and 50 ppm SA concentration. The catalyst was stable over 5 reaction cycles. The Fe-MgO catalyst was shown to have a surface area up to 171 m 2 /g and contain hematite (Fe2 O3 ) nanoparticles with octahedrally coordinated iron catalytic centers, as inferred from diffuse reflectance UV–vis measurements. Post-reaction catalyst characterization showed that some Fe 2+ was present in the catalyst due to the redox cycle during the chain initiation and propagation steps of the reaction. Graphical Abstract: ga1 Highlights: Fe doped MgO nanoparticles were used as a photocatalyst. Salicylic acid degradation is attributed to the heterogeneous photo-Fenton-like process. Salicylic acid completely oxidized in 2 hours with no intermediates. Fe-MgO displayed high stability over 5 catalytic cycles.