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Wang J, Liu J, Gao L, Xie D, Li C, Xiang L, Xiong H, Xie J, Zhang T, Pan Y. Investigation into enhanced performance of toluene and Hg 0 stimulative abatement over Cr-Mn oxides co-modified columnar activated coke. J Environ Sci (China) 2025; 148:88-106. [PMID: 39095204 DOI: 10.1016/j.jes.2023.09.011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2023] [Revised: 09/07/2023] [Accepted: 09/08/2023] [Indexed: 08/04/2024]
Abstract
In this study, a string of Cr-Mn co-modified activated coke catalysts (XCryMn1-y/AC) were prepared to investigate toluene and Hg0 removal performance. Multifarious characterizations including XRD, TEM, SEM, in situ DRIFTS, BET, XPS and H2-TPR showed that 4%Cr0.5Mn0.5/AC had excellent physicochemical properties and exhibited the best toluene and Hg0 removal efficiency at 200℃. By varying the experimental gas components and conditions, it was found that too large weight hourly space velocity would reduce the removal efficiency of toluene and Hg0. Although O2 promoted the abatement of toluene and Hg0, the inhibitory role of H2O and SO2 offset the promoting effect of O2 to some extent. Toluene significantly inhibited Hg0 removal, resulting from that toluene was present at concentrations orders of magnitude greater than mercury's or the catalyst was more prone to adsorb toluene, while Hg0 almost exerted non-existent influence on toluene elimination. The mechanistic analysis showed that the forms of toluene and Hg0 removal included both adsorption and oxidation, where the high-valent metal cations and oxygen vacancy clusters promoted the redox cycle of Cr3+ + Mn3+/Mn4+ ↔ Cr6+ + Mn2+, which facilitated the conversion and replenishment of reactive oxygen species in the oxidation process, and even the CrMn1.5O4 spinel structure could provide a larger catalytic interface, thus enhancing the adsorption/oxidation of toluene and Hg0. Therefore, its excellent physicochemical properties make it a cost-effective potential industrial catalyst with outstanding synergistic toluene and Hg0 removal performance and preeminent resistance to H2O and SO2.
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Affiliation(s)
- Jiajie Wang
- School of Resources Environment and Safety Engineering, University of South China, Hengyang 421001, China; National & Local Joint Engineering Research Center for Airborne Pollutants Control and Radioactivity Protection in Buildings, Hengyang 421001, China; Key Laboratory of Prefabricated Building Energy Saving Technology of Hunan Province, Hengyang 421001, China
| | - Jie Liu
- School of Resources Environment and Safety Engineering, University of South China, Hengyang 421001, China; National & Local Joint Engineering Research Center for Airborne Pollutants Control and Radioactivity Protection in Buildings, Hengyang 421001, China; Key Laboratory of Prefabricated Building Energy Saving Technology of Hunan Province, Hengyang 421001, China
| | - Lei Gao
- School of Resources Environment and Safety Engineering, University of South China, Hengyang 421001, China; National & Local Joint Engineering Research Center for Airborne Pollutants Control and Radioactivity Protection in Buildings, Hengyang 421001, China; Key Laboratory of Prefabricated Building Energy Saving Technology of Hunan Province, Hengyang 421001, China; College of Environmental Science and Engineering, Hunan University, Changsha 410082, China.
| | - Dong Xie
- National & Local Joint Engineering Research Center for Airborne Pollutants Control and Radioactivity Protection in Buildings, Hengyang 421001, China; Key Laboratory of Prefabricated Building Energy Saving Technology of Hunan Province, Hengyang 421001, China
| | - Caiting Li
- College of Environmental Science and Engineering, Hunan University, Changsha 410082, China
| | - Liping Xiang
- National & Local Joint Engineering Research Center for Airborne Pollutants Control and Radioactivity Protection in Buildings, Hengyang 421001, China; Key Laboratory of Prefabricated Building Energy Saving Technology of Hunan Province, Hengyang 421001, China
| | - Huiyu Xiong
- School of Resources Environment and Safety Engineering, University of South China, Hengyang 421001, China; National & Local Joint Engineering Research Center for Airborne Pollutants Control and Radioactivity Protection in Buildings, Hengyang 421001, China; Key Laboratory of Prefabricated Building Energy Saving Technology of Hunan Province, Hengyang 421001, China
| | - Jiaqi Xie
- School of Resources Environment and Safety Engineering, University of South China, Hengyang 421001, China; National & Local Joint Engineering Research Center for Airborne Pollutants Control and Radioactivity Protection in Buildings, Hengyang 421001, China; Key Laboratory of Prefabricated Building Energy Saving Technology of Hunan Province, Hengyang 421001, China
| | - Tianren Zhang
- National & Local Joint Engineering Research Center for Airborne Pollutants Control and Radioactivity Protection in Buildings, Hengyang 421001, China; Key Laboratory of Prefabricated Building Energy Saving Technology of Hunan Province, Hengyang 421001, China
| | - Yueguo Pan
- School of Resources Environment and Safety Engineering, University of South China, Hengyang 421001, China; National & Local Joint Engineering Research Center for Airborne Pollutants Control and Radioactivity Protection in Buildings, Hengyang 421001, China; Key Laboratory of Prefabricated Building Energy Saving Technology of Hunan Province, Hengyang 421001, China
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Oxidative Coupling of Methane for Ethylene Production: Reviewing Kinetic Modelling Approaches, Thermodynamics and Catalysts. Processes (Basel) 2021. [DOI: 10.3390/pr9122196] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Ethylene production via oxidative coupling of methane (OCM) represents an interesting route for natural gas upscaling, being the focus of intensive research worldwide. Here, OCM developments are analysed in terms of kinetic mechanisms and respective applications in chemical reactor models, discussing current challenges and directions for further developments. Furthermore, some thermodynamic aspects of the OCM reactions are also revised, providing achievable olefins yields in a wide range of operational reaction conditions. Finally, OCM catalysts are reviewed in terms of respective catalytic performances and thermal stability, providing an executive summary for future studies on OCM economic feasibility.
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