Issue 91, 2016, Issue in Progress

Selective catalytic oxidation of ammonia over MnOx–TiO2 mixed oxides

Abstract

The selective catalytic oxidation of ammonia to nitrogen (NH3–SCO) was investigated over MnOx–TiO2. The physicochemical properties of MnOx–TiO2 were characterized by XRD, O2-TPD, NH3-TPD, H2-TPR and XPS, and the reaction mechanism was studied by in situ DRIFTS. The addition of Mn into TiO2 accelerated the support phase transformation and the formation of Mn–O–Ti bonds. MnOx(0.25)–TiO2 showed the best performance in NH3–SCO, for which complete conversion of NH3 was obtained at 200 °C with the temperature window (180–300 °C) for N2 yield > 80%. The formation of Mn–O–Ti provided abundant oxygen vacancies which promoted the adsorption and dissociation of molecular oxygen to form active oxygen species. The finely dispersed MnOx species on the support favored NH3 adsorption. N2O was produced over the whole temperature range while NOx was produced only at high temperatures (>250 °C). N2O was formed from the combination of two HNO species at low temperatures, whereas it was formed from NH3 and nitrate/nitrite species reaction at high temperatures.

Graphical abstract: Selective catalytic oxidation of ammonia over MnOx–TiO2 mixed oxides

Article information

Article type
Paper
Submitted
21 Aug 2016
Accepted
29 Aug 2016
First published
01 Sep 2016

RSC Adv., 2016,6, 88117-88125

Selective catalytic oxidation of ammonia over MnOx–TiO2 mixed oxides

D. Song, X. Shao, M. Yuan, L. Wang, W. Zhan, Y. Guo, Y. Guo and G. Lu, RSC Adv., 2016, 6, 88117 DOI: 10.1039/C6RA20999H

To request permission to reproduce material from this article, please go to the Copyright Clearance Center request page.

If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given.

If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page.

Read more about how to correctly acknowledge RSC content.

Social activity

Spotlight

Advertisements