Publications by authors named "Xiaojin Han"

3 Publications

  • Page 1 of 1

Insight into the enhancing activity and stability of Ce modified VO/AC during cyclic desulfurization-regeneration-denitrification.

J Hazard Mater 2021 Sep 30;424(Pt B):127397. Epub 2021 Sep 30.

State Key Laboratory of Coal Conversion, Institute of Coal Chemistry, Chinese Academy of Sciences, Taiyuan 030001, China; University of Chinese Academy of Sciences, Beijing 100049, China. Electronic address:

Cyclic desulfurization-regeneration-denitrification over carbon-based catalysts is a promising technology for SO and NOx simultaneous elimination in steel industry. Regeneration is imperative to the long-term operation of the process, while the research is limited. In this work, Ce modified VO/AC catalyst (CeVOx/AC) with higher desulfurization and denitrification activity was prepared and the effect of cyclic regeneration was investigated. Results illustrated that the desulfurization and denitrification activity of CeVOx/AC gradually improved with increasing the regeneration cycles at the optimum regeneration temperature of 470 °C in N. The increasing Ce, V and oxygen vacancies, enhanced surface acidity and improved redox ability contributed to the catalytic activity of regenerated catalysts. For desulfurization, more SO transformed into HSO rather than to metal sulfates after cyclic regeneration. For denitrification, the improved redox ability accelerated the oxidation of NO to active NO, bridged nitrites and nitrates, and the enhanced acidity facilitated the NH adsorption, further generating more -NH and promoting the SCR activity of regenerated samples. The CeVOx/AC with good activity and regenerative stability shows great application potential in steel industry for the simultaneous SO and NOx removal.
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http://dx.doi.org/10.1016/j.jhazmat.2021.127397DOI Listing
September 2021

Effect of SCR Atmosphere on the Removal of Hg by a VO-CeO/AC Catalyst at Low Temperature.

Environ Sci Technol 2019 05 15;53(9):5521-5527. Epub 2019 Apr 15.

State Key Laboratory of Coal Conversion , Institute of Coal Chemistry Chinese Academy of Sciences , Taiyuan , Shanxi 030001 , P. R. China.

A series of VO-xCeO/AC (noted as V-Ce/AC) catalysts were synthesized by the impregnation method, which combined the advantage of AC and V-Ce. The effects of SCR atmosphere on Hg removal were systematically investigated at low temperature. The experimental results indicated that NO had a positive effect on Hg removal. In addition, an interesting experimental phenomenon was found that NH also showed a positive effect on Hg removal, which is different from many studies that have reported a negative effect of NH on Hg removal by other catalysts. NH-TPD experiment showed that there was no apparent competition between NH and Hg. An FT-IR gas analyzer and in situ DRIFTS were used to study the mechanism for the effect of NH on the catalyst surface and found that a small part of NH was overoxidized to NO in this catalytic system. O acted as a promoter in the whole process of NO and Hg removal. However, HO showed an inhibiting effect on Hg and NO removal over V-Ce/AC catalysts, which may be caused by the competitive adsorption of HO and pollutants (NO and Hg). Additionally, 1 V-8Ce/AC catalyst exhibited high stability ( E = 87.6%, E = 82.84%) after 72 h reaction in SCR atmosphere at 150 °C.
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http://dx.doi.org/10.1021/acs.est.8b07122DOI Listing
May 2019

Influence of calcination temperature on the properties of titanium oxide sulfur recovery catalysts.

J Nanosci Nanotechnol 2014 Sep;14(9):7181-8

To study the effect of calcination temperatures on the sulfur recovery catalysts, titanium oxide (TiO2), as sulfur recovery catalysts, were treated at four calcination temperatures of 300 degrees C, 500 degrees C, 700 degrees C and 900 degrees C. The structure of the catalysts were characterized by X-ray powder diffraction (XRD), Raman, transmission electron microscopy (TEM), Scanning electron microscopy (SEM), temperature thermogravimetry (TG) and differential scanning calorimetry (DSC). The results showed that with the calcination temperature increasing, the particle size of the TiO2 catalysts increases but the surface area and total pore volume decrease. The extent of reduction was more serious after calcination at 500 degrees C. Rutile phase were formed at calcination temperature about 700 degrees C. On the basis of these results, a scheme for the change of TiO2 with increasing calcination temperatures was proposed. The Claus catalytic activity of the TiO2 catalysts was evaluated in the traditional conditions. It was found that the Claus catalytic activity, which decreased a little when the calcination temperature was no more than 500 degrees C but much once the calcination temperature was more than 500 degrees C, was not only related to the surface area and pore volume, but also the phase of the TiO2. The activity of rutile was less than the anatase and a possible reaction pathway to reveal this mechanism was proposed.
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http://dx.doi.org/10.1166/jnn.2014.8953DOI Listing
September 2014
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