ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

Selective catalytic oxidation of ammonia into nitrogen and water vapour over transition metals modified Al2O3, TiO2 and ZrO2

Magdalena Jabƚońska

Faculty of Chemistry, Jagiellonian University, Ingardena 3, 30-060 Kraków, Poland

E-mail: Magdalena.Jablonskaw@gmail.com

Abstract: Copper or iron supported on commercially available oxides, such as γ-Al₂O₃, TiO₂ (anatase) and monoclinic tetragonal ZrO₂ (mt-ZrO₂) were tested as catalysts for selective catalytic oxidation of ammonia into nitrogen and water vapour (NH₃-SCO) in the low temperature range. Different commercial oxides were used in this study to determine the influence of the specific surface area, acidic nature of the support and crystalline phases as well as of the type of species and aggregation state of transition metals on the catalytic performance in selective ammonia oxidation. Copper modified oxide supports were found to be more active and selective to nitrogen than catalysts impregnated with iron. Activities of both transition metal modified samples decreased in the following order: mt-ZrO₂, TiO₂ (anatase), γ-Al₂O₃. Quantitative total ammonia conversion was achieved with the Cu/ZrO₂ catalytic system at 400°C. Characterisation techniques, e.g. H₂-temperature programmed reduction, UV-VIS-diffuse reflectance spectroscopy, suggest that easily reducible copper oxide species are important in achieving high catalytic performances at low temperatures

Keywords: oxide supports – selective oxidation of ammonia – NH3-SCO – copper – iron

Full paper is available at www.springerlink.com.

DOI: 10.1515/chempap-2015-0120

Chemical Papers 69 (9) 1141–1155 (2015)