Next Article in Journal
Study of the Influence of Shielding Gases on Laser Metal Deposition of Inconel 718 Superalloy
Previous Article in Journal
Influence of the Non-Schmid Effects on the Ductility Limit of Polycrystalline Sheet Metals
Previous Article in Special Issue
Composites of Laponite and Cu–Mn Hopcalite-Related Mixed Oxides Prepared from Inverse Microemulsions as Catalysts for Total Oxidation of Toluene
Article Menu
Issue 8 (August) cover image

Export Article

Open AccessFeature PaperArticle
Materials 2018, 11(8), 1387; https://doi.org/10.3390/ma11081387

Eco-Friendly Cavity-Containing Iron Oxides Prepared by Mild Routes as Very Efficient Catalysts for the Total Oxidation of VOCs

1
Departament d’Enginyeria Química, ETSE, Universitat de València, Av. Universitat, 46100 Burjassot, Valencia, Spain
2
Departamento de Química Inorgánica, Facultad de Ciencias Químicas, Universidad Complutense de Madrid, 28040 Madrid, Spain
3
Sepiolsa, Avda. del Acero, 14-16, Pol. UP-1 (Miralcampo), 19200 Azuqueca de Henares, Spain
4
Instituto de Carboquímica (ICB-CSIC), C/Miguel Luesma 4, 50018 Zaragoza, Spain
*
Authors to whom correspondence should be addressed.
Received: 20 July 2018 / Revised: 6 August 2018 / Accepted: 7 August 2018 / Published: 9 August 2018
View Full-Text   |   Download PDF [11744 KB, uploaded 9 August 2018]   |  

Abstract

Iron oxides (FeOx) are non-toxic, non-expensive and environmentally friendly compounds, which makes them good candidates for many industrial applications, among them catalysis. In the present article five catalysts based on FeOx were synthesized by mild routes: hydrothermal in subcritical and supercritical conditions (Fe-HT, Few200, Few450) and solvothermal (Fe-ST1 and Fe-ST2). The catalytic activity of these catalysts was studied for the total oxidation of toluene using very demanding conditions with high space velocities and including water and CO2 in the feed. The samples were characterized by X-ray diffraction (XRD), scanning and high-resolution transmission electron microscopy (SEM and HRTEM), X-ray photoelectron spectroscopy (XPS) and nitrogen adsorption-desorption isotherms. It was observed that the most active catalyst was a cavity-containing porous sample prepared by a solvothermal method with a relatively high surface area (55 m2 g−1) and constituted by flower-like aggregates with open cavities at the catalyst surface. This catalyst displayed superior performance (100% of toluene conversion at 325 °C using highly demanding conditions) and this performance can be maintained for several catalytic cycles. Interestingly, the porous iron oxides present not only a higher catalytic activity than the non-porous but also a higher specific activity per surface area. The high activity of this catalyst has been related to the possible synergistic effect of compositional, structural and microstructural features emphasizing the role of the surface area, the crystalline phase present, and the properties of the surface. View Full-Text
Keywords: volatile organic compounds (VOC); iron oxide; mild preparation routes; total oxidation; cavities volatile organic compounds (VOC); iron oxide; mild preparation routes; total oxidation; cavities
Figures

Graphical abstract

This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. (CC BY 4.0).

Supplementary material

SciFeed

Share & Cite This Article

MDPI and ACS Style

Sanchis, R.; Alonso-Domínguez, D.; Dejoz, A.; Pico, M.P.; Álvarez-Serrano, I.; García, T.; López, M.L.; Solsona, B. Eco-Friendly Cavity-Containing Iron Oxides Prepared by Mild Routes as Very Efficient Catalysts for the Total Oxidation of VOCs. Materials 2018, 11, 1387.

Show more citation formats Show less citations formats

Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.

Related Articles

Article Metrics

Article Access Statistics

1

Comments

[Return to top]
Materials EISSN 1996-1944 Published by MDPI AG, Basel, Switzerland RSS E-Mail Table of Contents Alert
Back to Top