The influence on SCR activity of the atomic structure of V2O5/TiO2 catalysts prepared by a mechanochemical method

Authors: Dong Wook Kwon, Kwang Hee Park, Sung Chang Hong

Abstract:
A catalyst prepared by a mechanochemical method enables changes in physico-chemical properties such as surface area, particle size and phase. Accordingly, after preparing the catalyst by synthesizing V₂O₅ and anatase TiO₂ with the mechanochemical method, a study on the selective catalytic reduction (SCR) reactive properties of NH₃ was performed. The dry ball milling method was shown to be compatible with the dry synthesis method of the SCR catalyst by combining V₂O₅ and TiO₂. The properties of the catalyst were studied using physio-chemical analyses, including BET surface area, X-ray diffraction (XRD), Raman spectroscopy, H₂ temperature programmed reduction (H₂-TPR), diffuse reflectance UV–VIS spectroscopy and X-ray photoelectron spectroscopy (XPS). The V₂O₅ crystallite peak decreased with increased milling time, and the monomeric species was formed. The maximum reducing temperature (Tmax) decreased by H2-TPR. Improvements in the redox capacity were identified by experiments in which O₂ was introduced and subsequently removed as well as by reoxidation analysis. Additionally, the presence of non-stoichiometric vanadium and an increased number of surface atoms were identified through the milling effect. A correlation was identified between the ratio of (V4+ +V3+)/V5+ and the catalyst NO_x conversion rate.

Keywords:
NOx removal
NH3 SCR
Dry ball milling
Mechanochemical

Published in: Applied catalysis A: General  (Volume 451, Pages 1-288, 31 January 2013)

Publisher: Elsevier

ISSN Information: 0926-860X

The influence on SCR activity of the atomic structure of V2O5/TiO2 catalysts prepared by a mechanochemical method

Bình luận của bạn

*

*

*

*

 Captcha

Gửi bình luận nhập lại