Probing toluene catalytic removal mechanism over supported Pt nano- and single-atom-catalyst

Zhiwei Wang; Huanggen Yang; Rui Liu; Shaohua Xie; Yuxi Liu; Hongxing Dai; Haibao Huang; Jiguang Deng

doi:10.1016/j.jhazmat.2020.122258

Probing toluene catalytic removal mechanism over supported Pt nano- and single-atom-catalyst

J Hazard Mater. 2020 Jun 15:392:122258. doi: 10.1016/j.jhazmat.2020.122258. Epub 2020 Feb 13.

Authors

Zhiwei Wang¹, Huanggen Yang², Rui Liu³, Shaohua Xie¹, Yuxi Liu¹, Hongxing Dai¹, Haibao Huang⁴, Jiguang Deng⁵

Affiliations

¹ Key Laboratory of Beijing on Regional Air Pollution Control, Beijing Key Laboratory for Green Catalysis and Separation, and College of Environmental and Energy Engineering, Beijing University of Technology, Beijing, 100124, China.
² Guangxi Key Laboratory of Agricultural Resources Chemistry and Biotechnology, College of Chemistry and Food Science, Yulin Normal University, Yulin, 537000, Guangxi, China.
³ State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China.
⁴ School of Environmental Science and Engineering, Sun Yat-Sen University, Guangzhou, 510275, China.
⁵ Key Laboratory of Beijing on Regional Air Pollution Control, Beijing Key Laboratory for Green Catalysis and Separation, and College of Environmental and Energy Engineering, Beijing University of Technology, Beijing, 100124, China. Electronic address: jgdeng@bjut.edu.cn.

PMID: 32092645
DOI: 10.1016/j.jhazmat.2020.122258

Abstract

Commercial TiO₂ supported 0.20 wt% Pt catalyst is obtained via the molten salt method, and both Pt nanoparticles and single atom Pt sites are observed. It exhibits high catalytic performance for toluene oxidation, with T₅₀ and T₉₀ being 173 and 183 °C, respectively. Reaction intermediates including benzene, p-xylene, o-xylene, benzaldehyde, phthalic acid, maleic anhydride, itaconic anhydride, acetone, and acetic acid, are detected during toluene oxidation. On this basis, likely toluene combustion reaction pathway is provided. Benzaldehyde is the most stable surface intermediate, and its oxidation can be rate-limiting for the entire toluene oxidation reaction. 2-10.0 vol% H₂O slightly inhibits the reaction by competing surface sites with the reactant, while it does not poison the catalyst. 2.5-10.0 vol% CO₂ slightly poisons the catalyst by surface carbonate formation, whereas 50 ppm SO₂ severely poisons the catalyst by sulfite/sulfate formation.

Keywords: Catalytic oxidation mechanism; Molten salt method; Pt; Single atom catalyst; Volatile organic compounds.

Publication types

Research Support, Non-U.S. Gov't