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Yao T, Long J, Duan Y, Gupta R, Xu Z. Effecting pattern study of SO 2 on Hg 0 removal over α-MnO 2 in-situ supported magnetic composite. JOURNAL OF HAZARDOUS MATERIALS 2023; 450:131088. [PMID: 36857829 DOI: 10.1016/j.jhazmat.2023.131088] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/21/2022] [Revised: 02/12/2023] [Accepted: 02/23/2023] [Indexed: 06/18/2023]
Abstract
α-MnO2 was in-situ supported onto silica coated magnetite nanoparticles (MagS-Mn) to study the adsorption and oxidation of Hg0 as well as the effecting patterns of SO2 and O2 on Hg0 removal. MagS-Mn showed Hg0 removal capacity of 1122.6 μg/g at 150 °C with the presence of SO2. Hg0 adsorption and oxidation efficiencies were 2.4% and 90.6%, respectively. Hg0 removal capability deteriorated at elevated temperatures. Surface oxygen and manganese chemistry analysis indicated that SO2 inhibited the Hg0 removal through consumption of adsorbed oxygen and reduction of high valence manganese. This inhibiting effect was observed to be counteracted by O2 at lower temperatures. O2 tended to compete with SO2 for active sites and further create additional adsorbed oxygen sites for Hg0 surface reaction via surface dissociative adsorption rather than replenish the active sites consumed by SO2. The high valence manganese was also preserved by O2 which was essential to Hg0 oxidation. The intervention of O2 in the inhibition of SO2 on Hg0 removal was weakened at temperatures higher than 250 °C. Aa a result, Hg0 tends to be catalytic oxidized in the condition of low reaction temperatures and with the presence of O2 over α-MnO2 oriented composites.
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Affiliation(s)
- Ting Yao
- Shanghai SUS Environment Co., LTD., Shanghai 201703, China; Key Laboratory of Energy Thermal Conversion and Control of Ministry of Education, School of Energy and Environment, Southeast University, Nanjing 210096, China; Department of Chemical and Materials Engineering, University of Alberta, Edmonton, AB T6G 1H9, Canada
| | - Jisheng Long
- Shanghai SUS Environment Co., LTD., Shanghai 201703, China
| | - Yufeng Duan
- Key Laboratory of Energy Thermal Conversion and Control of Ministry of Education, School of Energy and Environment, Southeast University, Nanjing 210096, China.
| | - Rajender Gupta
- Department of Chemical and Materials Engineering, University of Alberta, Edmonton, AB T6G 1H9, Canada
| | - Zhenghe Xu
- Department of Chemical and Materials Engineering, University of Alberta, Edmonton, AB T6G 1H9, Canada; Department of Materials Science and Engineering, Southern University of Science and Technology, Shenzhen 518055, China.
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Ma Y, Xu T, Wang J, Shi Y, Wang H, Xiong F, Xu H, Ma Y, Zhang H. Superior Hg 0 capture performance and SO 2 resistance of Co-Mn binary metal oxide-modified layered MCM-22 zeolite for SO 2-containing flue gas. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2021; 28:16447-16457. [PMID: 33389582 DOI: 10.1007/s11356-020-12214-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/13/2020] [Accepted: 12/22/2020] [Indexed: 06/12/2023]
Abstract
A Co-Mn binary metal oxide-modified layered MCM-22 zeolite was designed to capture gaseous elemental mercury (Hg0) from SO2-containing flue gas. The physicochemical properties of the Co-Mn/MCM-22 zeolite were characterized by XRD, FESEM, TEM, and XPS, and the results showed that MnO2 was highly dispersed on the surface and in the channel of MCM-22 zeolite. Co3O4 was loaded onto the surface of the MCM-22 zeolite via the stepwise ion exchange method to prevent SO2 poisoning of the MnO2 active site. The Hg0 removal efficiency increased from 54 to 83% at 300 °C with 10% Co loading on the 5% Mn/MCM-22 zeolite when 200 ppm of SO2 was introduced to the flue gas. The mechanism of Hg0 removal was mainly associated with catalytic oxidation and chemisorption. Mn4+ was the main active site for catalytic oxidation of Hg0 to Hg2+, and the surface adsorbed oxygen re-oxidized Mn3+ and combined with Hg2+ to form Hg-O-Mn, in which Mn acted as a bridge. Co3+ preferentially reacted with SO2 to form CoSO4, thereby protecting the Mn active sites for Hg0 capture. Therefore, Co-Mn/MCM-22 zeolite is a promising sorbent for the removal of Hg0 and SO2 resistance from SO2-containing flue gas.
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Affiliation(s)
- Yongpeng Ma
- Henan Collaborative Innovation Center of Environmental Pollution Control and Ecological Restoration, School of Material and Chemical Engineering, Zhengzhou University of Light Industry, 136 Science Avenue, Zhengzhou, 450001, China.
| | - Tengfei Xu
- Henan Collaborative Innovation Center of Environmental Pollution Control and Ecological Restoration, School of Material and Chemical Engineering, Zhengzhou University of Light Industry, 136 Science Avenue, Zhengzhou, 450001, China
| | - Jiandong Wang
- Henan Collaborative Innovation Center of Environmental Pollution Control and Ecological Restoration, School of Material and Chemical Engineering, Zhengzhou University of Light Industry, 136 Science Avenue, Zhengzhou, 450001, China
| | - Yanru Shi
- Henan Collaborative Innovation Center of Environmental Pollution Control and Ecological Restoration, School of Material and Chemical Engineering, Zhengzhou University of Light Industry, 136 Science Avenue, Zhengzhou, 450001, China
| | - Hongyan Wang
- Henan Collaborative Innovation Center of Environmental Pollution Control and Ecological Restoration, School of Material and Chemical Engineering, Zhengzhou University of Light Industry, 136 Science Avenue, Zhengzhou, 450001, China
| | - Feigen Xiong
- Henan Collaborative Innovation Center of Environmental Pollution Control and Ecological Restoration, School of Material and Chemical Engineering, Zhengzhou University of Light Industry, 136 Science Avenue, Zhengzhou, 450001, China
| | - Haomiao Xu
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Yunxia Ma
- Henan Key Laboratory of Environmental Monitoring Technology, Henan Environmental Monitoring Center, Zhengzhou, 450004, China
| | - Hongzhong Zhang
- Henan Collaborative Innovation Center of Environmental Pollution Control and Ecological Restoration, School of Material and Chemical Engineering, Zhengzhou University of Light Industry, 136 Science Avenue, Zhengzhou, 450001, China
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Editorial: Special Issue on “Advanced Strategies for Catalyst Design”. Catalysts 2020. [DOI: 10.3390/catal11010038] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
The word catalyst comes from the Greek κατα’λυσις, which means dissolution and was introduced in 1836 by the Swedish Berzelius [...]
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