Insight into the enhancing activity and stability of Ce modified V2O5/AC during cyclic desulfurization-regeneration-denitrification

Qiaoyan Li; Meisheng Liang; Xiaojin Han; Yaqin Hou; Zhanggen Huang

doi:10.1016/j.jhazmat.2021.127397

Insight into the enhancing activity and stability of Ce modified V₂O₅/AC during cyclic desulfurization-regeneration-denitrification

J Hazard Mater. 2022 Feb 15;424(Pt B):127397. doi: 10.1016/j.jhazmat.2021.127397. Epub 2021 Sep 30.

Authors

Qiaoyan Li¹, Meisheng Liang¹, Xiaojin Han², Yaqin Hou³, Zhanggen Huang⁴

Affiliations

¹ College of Environmental Science and Engineering, Taiyuan University of Technology, Taiyuan 030024, China.
² State Key Laboratory of Coal Conversion, Institute of Coal Chemistry, Chinese Academy of Sciences, Taiyuan 030001, China.
³ 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: houyaqin@sxicc.ac.cn.
⁴ 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: zghuang@sxicc.ac.cn.

PMID: 34638078
DOI: 10.1016/j.jhazmat.2021.127397

Abstract

Cyclic desulfurization-regeneration-denitrification over carbon-based catalysts is a promising technology for SO₂ 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 V₂O₅/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 N₂. The increasing Ce³⁺, V⁵⁺ and oxygen vacancies, enhanced surface acidity and improved redox ability contributed to the catalytic activity of regenerated catalysts. For desulfurization, more SO₂ transformed into H₂SO₄ rather than to metal sulfates after cyclic regeneration. For denitrification, the improved redox ability accelerated the oxidation of NO to active NO₂, bridged nitrites and nitrates, and the enhanced acidity facilitated the NH₃ adsorption, further generating more -NH₂ 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 SO₂ and NOx removal.

Keywords: CeVOx/AC; Cyclic regeneration; Denitrification; Desulfurization; Promoting mechanism.