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Steinhaus J, Pasel C, Bläker C, Bathen D. Impact of H 2O on the Adsorption of Hg 0 on Activated Carbon. ACS OMEGA 2021; 6:16989-17001. [PMID: 34250357 PMCID: PMC8264938 DOI: 10.1021/acsomega.1c01994] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/14/2021] [Accepted: 06/04/2021] [Indexed: 06/13/2023]
Abstract
In this work, the influence of water on the adsorption of mercury is systematically investigated on basic and washed activated carbons. Breakthrough curves were measured and temperature-programmed desorption (TPD) experiments were performed with mercury and water. Both physisorptive and chemisorptive interactions are relevant in the adsorption of mercury. The experiments show that the presence of water in the pores promotes chemisorption of mercury on washed activated carbons while there is little influence on chemisorption on basic materials. Washing exposes or forms oxygen functional groups that are chemisorptive sites for mercury. Obviously, effective chemisorption of mercury requires both the presence of water and of oxygen functional groups. As mercury chemisorption is preceded by a physisorptive step, higher physisorptive mercury loading at lower temperature (30 °C) enhances chemisorption though the reaction rate constant is smaller than at higher temperature (100 °C). Sequential adsorption and partial desorption of water at lower temperature changes the surface chemistry without inhibiting mercury physisorption. Here, the highest chemisorption rates were found. The number of desorption peaks in the TPD experiments corresponds to the number of adsorption and desorption mechanisms with different oxygen functional groups in the presence of water. The results of the TPD experiments were simulated using a transport model extended by an approach for chemisorption. The simulation results provide reaction parameters (activation energy, frequency factor, and reaction order) of each mechanism. As in many heterogeneously catalyzed reactions, the activation energy and the frequency factor are independent of mercury loading and increase with increasing temperature.
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Affiliation(s)
- Julian Steinhaus
- Chair
of Thermal Process Engineering, University
of Duisburg-Essen, Lotharstraße 1, D-47057 Duisburg, Germany
| | - Christoph Pasel
- Chair
of Thermal Process Engineering, University
of Duisburg-Essen, Lotharstraße 1, D-47057 Duisburg, Germany
| | - Christian Bläker
- Chair
of Thermal Process Engineering, University
of Duisburg-Essen, Lotharstraße 1, D-47057 Duisburg, Germany
| | - Dieter Bathen
- Chair
of Thermal Process Engineering, University
of Duisburg-Essen, Lotharstraße 1, D-47057 Duisburg, Germany
- Institute
of Energy and Environmental Technology, IUTA e. V., Bliersheimer Straße 60, D-47229 Duisburg, Germany
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Ambrosy JM, Pasel C, Luckas M, Bittig M, Bathen D. Influence of Oxygen on Hg 0 Adsorption on Non-Impregnated Activated Carbons. ACS OMEGA 2020; 5:17051-17061. [PMID: 32715190 PMCID: PMC7376566 DOI: 10.1021/acsomega.0c00338] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/27/2020] [Accepted: 06/05/2020] [Indexed: 06/11/2023]
Abstract
Both physisorptive and chemisorptive mechanisms play a role in the adsorption of mercury. The present publication investigates the influence of oxygen on the adsorption of Hg0 by breakthrough curve measurements and temperature-programmed desorption (TPD) experiments. The presence of O2 in the gas phase promotes chemisorption. Because of slow adsorption mechanisms, no equilibrium capacities of mercury chemisorption can be determined. For further investigations, coupled adsorption and desorption experiments with concentration swing adsorption and TPD experiments are performed. The results of TPD experiments are simulated and quantitatively evaluated by means of an extended transport model. From the number of desorption peaks, we obtain the number of different adsorption and desorption mechanisms. A detailed simulation of the peaks yields the reaction order, the frequency factor, and the activation energy of the desorption steps. The kinetic reaction parameters allow a mechanistic interpretation of the adsorption and desorption processes. Here, we suppose the formation of a complex between the carbon surface, mercury, and oxygen.
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Affiliation(s)
- Jonas M. Ambrosy
- Thermal
Process Engineering, University of Duisburg-Essen, Lotharstraße 1, D-47057 Duisburg, Germany
| | - Christoph Pasel
- Thermal
Process Engineering, University of Duisburg-Essen, Lotharstraße 1, D-47057 Duisburg, Germany
| | - Michael Luckas
- Thermal
Process Engineering, University of Duisburg-Essen, Lotharstraße 1, D-47057 Duisburg, Germany
| | - Margot Bittig
- Institute
of Energy and Environmental Technology, IUTA e. V., Bliersheimer Straße 60, D-47229 Duisburg, Germany
| | - Dieter Bathen
- Thermal
Process Engineering, University of Duisburg-Essen, Lotharstraße 1, D-47057 Duisburg, Germany
- Institute
of Energy and Environmental Technology, IUTA e. V., Bliersheimer Straße 60, D-47229 Duisburg, Germany
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Biswas S, Sen TK, Meikap BC. Experimental hydrodynamic and bed characteristics of co-current gas-liquid-solid three phase semifluidization with liquid as the continuous phase. PARTICULATE SCIENCE AND TECHNOLOGY 2019. [DOI: 10.1080/02726351.2019.1651586] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Affiliation(s)
- Subrata Biswas
- Department of Chemical Engineering, Indian Institute of Technology, Kharagpur, India
- Department of Chemical Engineering, Curtin University, Perth, Australia
| | - Tushar Kanti Sen
- Department of Chemical Engineering, Curtin University, Perth, Australia
| | - Bhim Charan Meikap
- Department of Chemical Engineering, Indian Institute of Technology, Kharagpur, India
- Department of Chemical Engineering, Curtin University, Perth, Australia
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Ambrosy JM, Pasel C, Luckas M, Bittig M, Bathen D. A Detailed Investigation of Adsorption Isotherms, Enthalpies, and Kinetics of Mercury Adsorption on Nonimpregnated Activated Carbon. Ind Eng Chem Res 2019. [DOI: 10.1021/acs.iecr.8b05932] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Jonas M. Ambrosy
- Thermal Process Engineering, University of Duisburg-Essen, Lotharstraße 1, Duisburg D-47057, Germany
| | - Christoph Pasel
- Thermal Process Engineering, University of Duisburg-Essen, Lotharstraße 1, Duisburg D-47057, Germany
| | - Michael Luckas
- Thermal Process Engineering, University of Duisburg-Essen, Lotharstraße 1, Duisburg D-47057, Germany
| | - Margot Bittig
- Institute of Energy and Environmental Technology, IUTA e. V., Bliersheimer Straße 60, Duisburg D-47229, Germany
| | - Dieter Bathen
- Thermal Process Engineering, University of Duisburg-Essen, Lotharstraße 1, Duisburg D-47057, Germany
- Institute of Energy and Environmental Technology, IUTA e. V., Bliersheimer Straße 60, Duisburg D-47229, Germany
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Wei Y, Yu D, Tong S, Jia CQ. Effects of H ₂SO₄ and O ₂ on Hg⁰ uptake capacity and reversibility of sulfur-impregnated activated carbon under dynamic conditions. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2015; 49:1706-1712. [PMID: 25590356 DOI: 10.1021/es504178x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Powder activated carbon (AC) injection is widely considered as the most viable technology for removing gaseous elemental mercury (Hg(0)) in flue gases of coal-fired power plants. However, sulfuric acid (H2SO4) can form on the external and internal surfaces of AC particles due to the presence of sulfur oxides, nitrogen oxides, oxygen, and moisture in flue gases. This work focuses on the effects of H2SO4 and O2 on the Hg(0) uptake capacity and reversibility of sulfur impregnated activated carbon (SIAC) under dynamic conditions. Experiments were conducted with 25 μg-Hg(0)/m(3) of nitrogen or air, using a semicontinuous flow fixed-bed reactor kept at 120 or 180 °C. H2SO4 had a profound hindering effect on Hg(0) uptake due to pore blockage. O2 significantly enhanced Hg(0) uptake and its reversibility, via the oxidation of Hg(0) which facilitated chemisorption and the subsequent physisorption onto chemically adsorbed Hg. Absorption of Hg in H2SO4 was unlikely a significant contributor, when Hg(0) concentrations were at levels of typical power plants (tens of ppb). The reversibility of and relative contributions of physisorption and chemisorption to Hg(0) uptake would change with Hg(0) concentrations in flue gases. These findings could be significant in developing a complete solution for Hg capture where the handling of spent sorbent materials and the possible secondary pollution need to be considered.
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Affiliation(s)
- Yuanyang Wei
- Department of Chemical Engineering & Applied Chemistry, University of Toronto , Toronto, Ontario, Canada M5S 3E5
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Cheng X, Bi XT. Modeling and simulation of nitrogen oxides adsorption in fluidized bed reactors. Chem Eng Sci 2013. [DOI: 10.1016/j.ces.2013.03.052] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Lu CY, Rau JY, Chen JC, Huang ST, Wey MY. Removal of NO and fly ash over a carbon supported catalyst: Effects of fly ash concentration and operating time. POWDER TECHNOL 2013. [DOI: 10.1016/j.powtec.2013.02.002] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Rau JY, Chen JC, Huang ST, Hung WT, Wey MY. Removals of fly ash and NO in a fluidized-bed reactor with CuO/activated carbon catalysts. JOURNAL OF HAZARDOUS MATERIALS 2011; 187:190-198. [PMID: 21288639 DOI: 10.1016/j.jhazmat.2011.01.018] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/30/2010] [Revised: 12/15/2010] [Accepted: 01/04/2011] [Indexed: 05/30/2023]
Abstract
This study investigates the effects of fly ash compositions (SiO(2) and Al(2)O(3)), particle sizes (4-10 μm and 40 μm), and concentrations on the simultaneous removals of fly ash and NO using a fluidized-bed catalyst reactor. Experimental results show that the removal efficiencies of fly ash and NO at particle concentrations of 968-11,181 mg m(-3) are 71-97% and 42-57%, respectively. SiO(2) particles have more influences than Al(2)O(3) particles on the performances of fluidized-bed CuO/AC catalyst. As the concentration of fine particle increases, the pores and active sites on catalyst surface are obstructed and therefore the activities of catalysts are depressed.
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Affiliation(s)
- Jui-Yeh Rau
- Department of Environmental Engineering, National Chung Hsing University, Taichung 40227, Taiwan, ROC
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Jena H, Roy G, Meikap B. Hydrodynamics of regular particles in a liquid–solid semi-fluidized bed. POWDER TECHNOL 2009. [DOI: 10.1016/j.powtec.2009.07.022] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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Rau JY, Chen JC, Wey MY, Lin MD. Effects of H2O and Particles on the Simultaneous Removal of SO2 and Fly Ash Using a Fluidized-Bed Sorbent/Catalyst Reactor. Ind Eng Chem Res 2009. [DOI: 10.1021/ie900843f] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Jui-Yeh Rau
- Department of Environmental Engineering, National Chung Hsing University, Taichung 402, Taiwan, Republic of China, and Department of Safety, Health and Environmental Engineering, HungKuang University, Taichung 433, Taiwan, Republic of China
| | - Jyh-Cherng Chen
- Department of Environmental Engineering, National Chung Hsing University, Taichung 402, Taiwan, Republic of China, and Department of Safety, Health and Environmental Engineering, HungKuang University, Taichung 433, Taiwan, Republic of China
| | - Ming-Yen Wey
- Department of Environmental Engineering, National Chung Hsing University, Taichung 402, Taiwan, Republic of China, and Department of Safety, Health and Environmental Engineering, HungKuang University, Taichung 433, Taiwan, Republic of China
| | - Min-Der Lin
- Department of Environmental Engineering, National Chung Hsing University, Taichung 402, Taiwan, Republic of China, and Department of Safety, Health and Environmental Engineering, HungKuang University, Taichung 433, Taiwan, Republic of China
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Ho T, Shetty S, Chu H, Lin C, Hopper J. Simulation of mercury emission control by activated carbon under confined-bed operations. POWDER TECHNOL 2008. [DOI: 10.1016/j.powtec.2007.02.023] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Ho T, Lee Y, Chu H, Lin C, Hopper J. Modeling of mercury desorption from activated carbon at elevated temperatures under fluidized/fixed bed operations. POWDER TECHNOL 2005. [DOI: 10.1016/j.powtec.2004.11.034] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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