(560gb) The Synergistic Effect of Copper and Niobium Species on a Novel Ti-Based Ternary Oxide Catalyst for NOx Removal with NH3

Authors: 
Wang, X., Key Laboratory of Biomass Chemical Engineering of Ministry of Education, Institute of Industrial Ecology and Environment, College of Chemical and Biological Engineering, Zhejiang University
Li, S. J., Zhejiang University
Li, W., Zhejiang University
Shi, Y., Zhejiang University

line-height:20.0pt;layout-grid-mode:char">The
synergistic effect of copper and niobium species on a novel Ti-based ternary oxide
catalyst for NOx removal with NH3

line-height:12.0pt;layout-grid-mode:char"> 11.0pt;font-family:" times new roman>Xiaoxiang Wang, Sujing Li*, Wei Li*, Yao Shi

layout-grid-mode:char"> " times new roman>Key Laboratory of Biomass Chemical
Engineering of Ministry of Education, Institute of
Industrial Ecology and Environment,
College of Chemical and Biological Engineering, Zhejiang
University, Hangzhou 310027, China

white">Abstract:
As
the traditional VW(Mo)Ti catalyst existed some drawbacks using in NH3-SCR
reaction, it¡¯s necessary to develop new TiO2-based alternative
catalysts for NOx abatement. 0.8%Cu/Ti2NbOx as
a novel catalyst was developed and investigated. The NOx conversion
and N2 selectivity maintained upon 90% and 97% respectively in the
temperature range of 250oC-425oC under a high gas hourly
space velocity (GHSV) of 177,000h-1. Water vapor or SO2
would not pose any negative effect on the SCR activity. Also, 0.8%Cu/Ti2NbOx
exhibited an excellent hydrothermal stability and alkali mental resistance. The
performance characterization indicated 0.8%Cu/Ti2NbOx was
a promising candidate for the NH3-SCR catalyst in the future
practical application. Besides, an array of analytical techniques were employed
to elucidate the correlations among the performance-structure-property and the
reaction mechanism over 0.8%Cu/Ti2NbOx catalyst. The
introduction of niobium oxide increased the surface area of TiO2 and
decreased the crystallite size, promoting the high dispersion of copper
species. Meanwhile, the total acidity and the amount of surface active oxygen
over the catalyst were increased by the addition of niobium oxide. Copper
species mainly existing in the state of isolated Cu2+ and
non-isolated Cu+ enhanced the redox capability of the catalyst, resulting
in an excellent catalytic performance. There is a promotional synergistic
effect between copper and niobium in 0.8%Cu/Ti2NbOx
catalyst during the catalytic reaction. Furthermore, the reaction pathway over
0.8%Cu/Ti2NbOx catalyst followed both Eley-Rideal
mechanism and Langmuir-Hinshelwood mechanism at 225oC.

white">Key
words:
Cu/Nb-Ti
mixed oxide catalyst; Synergistic effect; Reaction pathway

 

Fig.1.
NOx conversion and N2 selectivity over TiO2,
Cu/TiO2 and Cu/Ti2NbOx catalysts. Reaction
conditions: [NH3] = [NO] = 500 ppm, [O2] = 5%, total flow
rate = 500 mL min-1, GHSV = 177,000 h-1 and N2
as balance.

 

References

text-indent:-18.0pt;layout-grid-mode:char"> font-family:" times new roman>[1] X.X. Wang, Y. Shi, S. J. Li*,
W. Li, Appl. Catal. B: Environ., 220 (2018) 234-250.

12.0pt;line-height:150%;font-family:" times new roman>[2] X.X. Wang,
Q.L. Cong, L. Chen, Y. Shi, Y. Shi, S.J. Li*, W. Li*,
Appl. Catal. B: Environ., 246 (2019) 166-179.

" times new roman>