Issue 67, 2020

A study on the selective catalytic reduction of NOx by ammonia on sulphated iron-based catalysts

Abstract

A series of sulphated iron-based catalysts was prepared via an impregnation method by changing the loading content of Fe3+ and SO42− on ZrO2, and their performance in the selective catalytic reduction (SCR) of NOx by ammonia was investigated. The NOx conversion exhibited large differences among the sulphated iron-based catalysts. To explore the synergistic mechanism of iron and sulphates, XRD, BET, H2-TPR, XPS, TPD and in situ DRIFTS were used to characterize the catalysts, and it was found that among all the catalysts, the NOx conversion by Fe2SZr was greater than 90% at 350–450 °C. The results indicated that the interaction between Fe3+ and SO42− can have an effect on the redox ability, acid sites, and adsorption of NOx and NH3. With an increase in the content of Fe3+, the redox activity of the catalyst and the adsorption of ammonia improved at medium and low temperatures. However, at higher temperatures, an increase in Fe3+ led to a decrease in the conversion of NOx due to the enhanced oxidation of NH3. At medium and low temperatures, an increase in the content of SO42− decreased the concentration of Fe3+ on the surface of the catalyst and inhibited the adsorption of NOx and NH3. The addition of SO42− reduced the redox activity of the catalyst and inhibited the oxidation reaction of NH3, which follows the Eley–Rideal mechanism at high temperatures, further enhancing the SCR activity of the FexSyZr catalyst.

Graphical abstract: A study on the selective catalytic reduction of NOx by ammonia on sulphated iron-based catalysts

Article information

Article type
Paper
Submitted
03 Aug. 2020
Accepted
08 Okt. 2020
First published
10 Nov. 2020
This article is Open Access
Creative Commons BY-NC license

RSC Adv., 2020,10, 40948-40959

A study on the selective catalytic reduction of NOx by ammonia on sulphated iron-based catalysts

C. Liu, H. Wang, Y. Bi and Z. Zhang, RSC Adv., 2020, 10, 40948 DOI: 10.1039/D0RA06697D

This article is licensed under a Creative Commons Attribution-NonCommercial 3.0 Unported Licence. You can use material from this article in other publications, without requesting further permission from the RSC, provided that the correct acknowledgement is given and it is not used for commercial purposes.

To request permission to reproduce material from this article in a commercial publication, 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 commercial 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