In:
Asia-Pacific Journal of Chemical Engineering, Wiley, Vol. 16, No. 1 ( 2021-01)
Abstract:
The Mn‐Fe‐Sn/TiO 2 (MFST) catalysts for NO and Hg co‐removal with SO 2 resistance at low temperature were prepared by the impregnation method under different calcination temperatures (300, 400, 500, and 600°C). The influences of calcination temperatures on SO 2 resistance and of SO 2 concentration on both denitration and demercuration performances of the Mn‐Fe‐Sn/TiO 2 catalysts were investigated in a fixed‐bed reaction system. Surface physicochemical characteristics and SO 2 resistance mechanism of MFST catalysts were analyzed by means of Brunauer–Emmett–Teller (BET), X‐ray diffraction (XRD), H 2 ‐temperature‐programmed reduction (H 2 ‐TPR), and X‐ray photoelectron spectroscopy (XPS). The results showed that the NO and Hg 0 removal efficiency of the MFST catalysts was not affected by reaction temperature between 200–280°C in the absence of SO 2 . However, the NO and Hg 0 removal efficiency was affected mostly in SO 2 ‐containing atmosphere. Appropriate calcination temperature can alleviate SO 2 poisoning and improve catalytic activity. When the calcination temperature was below 500°C, MFST catalysts have good resistance to the SO 2 , and it was found that at calcination temperature of 400°C, the NO and Hg 0 removal efficiency had the minimum decay from 95% to 70% and 99% to 93% at 700 ppm SO 2 , respectively, which was higher than that of other catalysts. That was mainly due to the abundant BET surface area and pore parameters and the high ratio of Mn 4+ /(Mn 4+ + Mn 3+ ), Fe 3+ /(Fe 3+ + Fe 2+ ), and O α /(O α + O β ) on catalyst surface. At lower calcination temperature (≤400°C), the metal active ingredient did not calcined sufficiently that made the NO and Hg 0 removal efficiency declined. While at higher calcination temperature ( 〉 400°C), the catalyst tended to agglomeration and MnO 2 was converted into Mn 2 O 3 gradually. Furthermore, doping Fe and Sn can effectively reduce the consumption of Mn 4+ , which greatly improved the catalytic activity and the SO 2 resistance.
Type of Medium:
Online Resource
ISSN:
1932-2135
,
1932-2143
Language:
English
Publisher:
Wiley
Publication Date:
2021
detail.hit.zdb_id:
2276947-X
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