Intrinsic catalytic properties of extruded clay honeycomb monolith toward complete oxidation of air pollutants

摘要

The present work highlights the intrinsic catalytic properties of extruded clay honeycomb monolith toward complete oxidation of various air pollutants namely CO, methane, propane, acetylene, propene, n-butene, methanol, ethanol, n-propanol, n-butanol, acetone, dimethyl ether, benzene, toluene, o-xylene, monochlorobenzene and 1,2-dichlorobenzene. Total catalytic conversion was achieved for all tested compounds with different behaviors depending on pollutants' structural and chemical nature. The comparison of T-50 values obtained from light-off curves allowed the establishment of the following reactivity sequence: ketone > alcohol > ether > CO> allcyne > aromatic > alkene > chlorinated aromatic > alkane. The intrinsic catalytic performances of the natural clay was ascribed to the implication of a quite complex mixture constituted by OH groups (Bronsted acids) and coordinately-unsaturated cations, such as Al3+, Fe3+ and Fe2+ (Lewis acids). Hence, the combination of the clay's intrinsic catalytic performances and easier extrudability suggests a promissory potential for application in air pollution control. (C) 2015 Elsevier B.V. All rights reserved.