Flame synthesized nanoscale catalyst (CuCeWTi) with excellent Hg0 oxidation activity and hydrothermal resistance

Guoliang Li; Sen Shao; Shuxiao Wang; Xiaoqing You; Junhua Li; Qingru Wu; Liwen Xu; Minneng Wen; Yu Wang; Kaiyun Liu

doi:10.1016/j.jhazmat.2020.124427

Flame synthesized nanoscale catalyst (CuCeWTi) with excellent Hg⁰ oxidation activity and hydrothermal resistance

J Hazard Mater. 2021 Apr 15:408:124427. doi: 10.1016/j.jhazmat.2020.124427. Epub 2020 Nov 1.

Authors

Guoliang Li¹, Sen Shao², Shuxiao Wang³, Xiaoqing You⁴, Junhua Li¹, Qingru Wu¹, Liwen Xu¹, Minneng Wen¹, Yu Wang¹, Kaiyun Liu¹

Affiliations

¹ State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China; State Environmental Protection Key Laboratory of Sources and Control of Air Pollution Complex, Beijing 100084, China.
² Key Laboratory for Thermal Science and Power Engineering of the Ministry of Education, Tsinghua University, Beijing 100084, China; Center for Combustion Energy, Tsinghua University, Beijing 100084, China.
³ State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China; State Environmental Protection Key Laboratory of Sources and Control of Air Pollution Complex, Beijing 100084, China. Electronic address: shxwang@tsinghua.edu.cn.
⁴ Key Laboratory for Thermal Science and Power Engineering of the Ministry of Education, Tsinghua University, Beijing 100084, China; Center for Combustion Energy, Tsinghua University, Beijing 100084, China. Electronic address: xiaoqing.you@tsinghua.edu.cn.

PMID: 33189470
DOI: 10.1016/j.jhazmat.2020.124427

Abstract

In view of poor hydrothermal resistance of impregnation prepared catalysts (Cu5Ce5W9Ti-I), this paper aims to enhance thermal and hydrothermal resistance of Cu/Ce based catalysts for Hg⁰ oxidation via flame synthesis technology. The result found that the flame synthesis method could form nanoscale Cu10Ce10W9Ti-F particles with smaller lattice size (8-25 nm), more stable carrier structure and more oxygen vacancies. The inter-doping and inter-substitution of Ce, Cu and Ti oxides created more oxygen vacancies (Ce³⁺) and L-sites (O^2-). Furthermore, the carrier TiO₂ of Cu10Ce10W9Ti-F existed in form of highly thermostable rutile rather than anatase. High Hg⁰ oxidation efficiency (MOE) of 83.9-99.7% at 100-450 °C proved excellent oxidation activity of Cu10Ce10W9Ti-F catalyst. Moreover, the thermal and hydrothermal treatment (700 °C) only decreased MOE by less than 5% since L-sites kept fine thermostability of Cu10Ce10W9Ti-F. The flame synthesis was proven to be a promising catalyst preparation method to enhance thermal and hydrothermal resistance.

Keywords: Flame synthesis; Hydrothermal resistance; Mercury oxidation; Nano materials.