Winning Combination of Cu and Fe Oxide Clusters with an Alumina Support for Low-Temperature Catalytic Oxidation of Volatile Organic Compounds

A gamma-aluminasupport functionalized with transition metalsis one of the most widely used industrial catalysts for the totaloxidation of volatile organic compounds (VOCs) as air pollutants athigher temperatures (280-450 degrees C). By rational design ofa bimetal CuFe-gamma-alumina catalyst, synthesized from a dawsonitealumina precursor, the activity in total oxidation of toluene as amodel VOC at a lower temperature (200-380 degrees C) is achieved.A fundamental understanding of the catalyst and the reaction mechanismis elucidated by advanced microscopic and spectroscopic characterizationsas well as by temperature-programmed surface techniques. The natureof the metal-support bonding and the optimal abundance betweenCu-O-Al and Fe-O-Al species in the catalystsleads to synergistic catalytic activity promoted by small amountsof iron (Fe/Al = 0.005). The change in the metal oxide-clusteralumina interface is related to the nature of the surfaces to whichthe Cu atoms attach. In the most active catalyst, the CuO6 octahedra are attached to 4 Al atoms, while in the less active catalyst,they are attached to only 3 Al atoms. The oxidation of toluene occursvia the Langmuir-Hinshelwood mechanism. The presented materialintroduces a prospective family of low-cost and scalable oxidationcatalysts with superior efficiency at lower temperatures.

Automated summary

By studying a bimetal CuFe-gamma-alumina catalyst, researchers have achieved catalytic activity in the total oxidation of toluene, a model VOC, at lower temperatures. They have also gained a deeper understanding of the catalyst and the reaction mechanism through advanced microscopic and spectroscopic characterizations. The optimal abundance of Cu-O-Al and Fe-O-Al species in the catalysts leads to synergistic catalytic activity, and the attachment of CuO6 octahedra to specific Al atoms affects the catalyst's activity. The oxidation of toluene occurs via the Langmuir-Hinshelwood mechanism. This research introduces a potential family of low-cost and scalable oxidation catalysts with superior efficiency at lower temperatures.