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Masod MB, El-Fiqi A, Ebiad MA. Encapsulation of activated carbon into calcium alginate microspheres toward granular-activated carbon adsorbents for elemental mercury capture from natural gas. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2023:10.1007/s11356-023-28176-7. [PMID: 37318735 DOI: 10.1007/s11356-023-28176-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/26/2023] [Accepted: 06/05/2023] [Indexed: 06/16/2023]
Abstract
Activated carbon (AC) is an effective adsorbent for removing environmental pollutants. However, the traditional powder form of AC shows difficulty in handling during application which widely limits its utilization on the industrial scale. Herein, to avoid such limitation, traditional AC powder was encapsulated into calcium alginate (CA) microspheres. Calcium alginate/activated carbon (CAA) composite microspheres were prepared via cross-linking of sodium alginate/activated carbon composite solutions in a calcium chloride solution. Furthermore, in order to boost adsorption affinity of CAA composite microspheres toward elemental mercury (Hg°), ammonium iodide (NH4I)-treated calcium alginate/activated carbon (NCA) composite microspheres were obtained by a simple impregnation method using NH4I treatment. The morphological, structural, and textural properties of the microspheres were characterized and their Hg° adsorptive capacity was tested at different temperatures. Interestingly, the maximum adsorption capacity of NCA adsorbent composite microspheres was determined as 36,056.5 μg/g at a flow rate of 250 mL/min, temperature of 25 °C, and 500 μg/Nm3 of Hg° initial concentration. The Gibbs free energy (ΔG°) for NCA adsorbent composite microspheres varied from - 8.59 to - 10.54 kJ/mol indicating a spontaneous adsorption process with an exothermic nature. The experimental Hg° breakthrough curve correlated well with Yoon‒Nelson and Thomas models. The breakthrough time (tb) and equilibrium time (te) were found to be 7.5 days and 23 days, respectively. Collectively, the findings of this work indicate a good feasibility of using NCA composite microspheres as potential adsorbents for removing Hg° from natural gas.
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Affiliation(s)
- Mohamed Bakry Masod
- Egyptian Petroleum Research Institute (EPRI), Nasr City, 11727, Cairo, Egypt
| | - Ahmed El-Fiqi
- Glass Research Department, National Research Centre, Giza, 12622, Cairo, Egypt.
| | - Mohamed A Ebiad
- Egyptian Petroleum Research Institute (EPRI), Nasr City, 11727, Cairo, Egypt
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Saheed IO, Oh WD, Suah FBM. Chitosan modifications for adsorption of pollutants - A review. JOURNAL OF HAZARDOUS MATERIALS 2021; 408:124889. [PMID: 33418525 DOI: 10.1016/j.jhazmat.2020.124889] [Citation(s) in RCA: 153] [Impact Index Per Article: 51.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/16/2020] [Revised: 12/14/2020] [Accepted: 12/15/2020] [Indexed: 05/18/2023]
Abstract
In recent times, research interest into the development of biodegradable, cost-effective and environmental friendly adsorbents with favourable properties for adsorption of pollutants is a challenge. Modification of chitosan via different physical and chemical methods have gained attention as a promising approach for removing organic (such as dyes and pharmaceuticals) and inorganic (such as metal/metal ions) pollutants from aqueous medium. In this regard, researchers have reported grafting and cross-linking approach among others as a potentially useful method for chitosan's modification for improved adsorption efficiency with respect to pollutant uptake. This article reviews the trend in chitosan modification, with regards to the summary of some recently published works on modification of chitosan and their adsorption application in pollutants (metal ion, dyes and pharmaceuticals) removal from aqueous medium. The review uniquely highlights some common cross-linkers and grafting procedures for chitosan modification, their influence on structure and adsorption capacity of modified-chitosan with respect to pollutants removal. Findings revealed that the performance of modified chitosan for adsorption of pollutants depends largely on the modification method adopted, materials used for the modification and adsorption experimental conditions. Cross-linking is commonly utilized for improving the chemical and mechanical stabilities of chitosan but usually decreases adsorption capacity of chitosan/modified-chitosan for adsorption of pollutants. However, literature survey revealed that adsorption capacity of cross-linked chitosan based materials have been enhanced in recently published works either by grafting, incorporation of solid adsorbents (e.g metals, clays and activated carbon) or combination of both prior to cross-linking.
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Affiliation(s)
- Ismaila Olalekan Saheed
- Green Analytical Chemistry Laboratory, School of Chemical Sciences, Universiti Sains Malaysia, Minden, Pulau Pinang 11800, Malaysia; Department of Chemical, Geological and Physical Sciences, Kwara State University, Malete, P.M.B 1530, Ilorin, Nigeria
| | - Wen Da Oh
- Green Analytical Chemistry Laboratory, School of Chemical Sciences, Universiti Sains Malaysia, Minden, Pulau Pinang 11800, Malaysia
| | - Faiz Bukhari Mohd Suah
- Green Analytical Chemistry Laboratory, School of Chemical Sciences, Universiti Sains Malaysia, Minden, Pulau Pinang 11800, Malaysia
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3
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Zhu Z, Xiang M, Li P, Shan L, Zhang P. Surfactant-modified three-dimensional layered double hydroxide for the removal of methyl orange and rhodamine B: Extended investigations in binary dye systems. J SOLID STATE CHEM 2020. [DOI: 10.1016/j.jssc.2020.121448] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
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4
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Ebiad MA, Abd El-Hafiz DR, Masod MB. β-FeOOH/C nanocomposite for elemental mercury removal as a new approach to environmental and natural gas processes. JOURNAL OF NATURAL GAS SCIENCE AND ENGINEERING 2020; 80:103383. [DOI: 10.1016/j.jngse.2020.103383] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/02/2023]
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Das S, Samanta A, Kole K, Gangopadhyay G, Jana S. MnO2 flowery nanocomposites for efficient and fast removal of mercury(ii) from aqueous solution: a facile strategy and mechanistic interpretation. Dalton Trans 2020; 49:6790-6800. [DOI: 10.1039/d0dt01054e] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
MnO2 flowery nanocomposites were explored as a novel and cost effective nanoadsorbent for the fast and efficient extraction of toxic inorganic contaminants from aqueous solution.
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Affiliation(s)
- Sankar Das
- Department of Chemical
- Biological & Macro-Molecular Sciences
- S. N. Bose National Centre for Basic Sciences
- Kolkata 700 106
- India
| | - Arnab Samanta
- Department of Chemical
- Biological & Macro-Molecular Sciences
- S. N. Bose National Centre for Basic Sciences
- Kolkata 700 106
- India
| | - Kanika Kole
- Technical Research Centre
- S. N. Bose National Centre for Basic Sciences
- Kolkata 700 106
- India
| | - Gautam Gangopadhyay
- Department of Chemical
- Biological & Macro-Molecular Sciences
- S. N. Bose National Centre for Basic Sciences
- Kolkata 700 106
- India
| | - Subhra Jana
- Department of Chemical
- Biological & Macro-Molecular Sciences
- S. N. Bose National Centre for Basic Sciences
- Kolkata 700 106
- India
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6
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Bhatt R, P P. A chitosan-thiomer polymer for highly efficacious adsorption of mercury. Carbohydr Polym 2019; 207:663-674. [DOI: 10.1016/j.carbpol.2018.12.018] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2018] [Revised: 12/03/2018] [Accepted: 12/09/2018] [Indexed: 12/29/2022]
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7
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Bhatt R, Kushwaha S, Bojja S, Padmaja P. Chitosan-Thiobarbituric Acid: A Superadsorbent for Mercury. ACS OMEGA 2018; 3:13183-13194. [PMID: 31458039 PMCID: PMC6644366 DOI: 10.1021/acsomega.8b01837] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/31/2018] [Accepted: 09/20/2018] [Indexed: 06/10/2023]
Abstract
In the present investigation, chitosan (CH) was supramolecularly cross-linked with thiobarbituric acid to form CT. CT was well characterized by UV, scanning electron microscopy-energy-dispersive X-ray analysis, Fourier transform infrared, NMR, differential scanning calorimetry, thermogravimetric analysis, and X-ray diffraction analyses, and its adsorption potential for elemental mercury (Hg0), inorganic mercury (Hg2+), and methyl mercury (CH3Hg+) was investigated. Adsorption experiments were conducted to optimize the parameters for removal of the mercury species under study, and the data were analyzed using Langmuir, Freundlich, and Temkin adsorption isotherm models. CT was found to have high adsorption capacities of 1357.69, 2504.86, and 2475.38 mg/g for Hg0, Hg2+, and CH3Hg+, respectively. The adsorbent CT could be reused up to three cycles by eluting elemental mercury using 0.01 N thiourea, inorganic mercury using 0.01 N perchloric acid, and methyl mercury with 0.2 N NaCl.
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Affiliation(s)
- Rahul Bhatt
- Department
of Chemistry, Faculty of Science, M. S.
University of Baroda, Sayajigunj, Vadodara 390002, Gujarat, India
| | - Shilpi Kushwaha
- Organic
Chemistry Division, CSIR-National Chemical
Laboratory, Dr. Homi Bhabha Road, Pashan, Pune 411008, Maharashtra, India
| | - Sreedhar Bojja
- Department
of Inorganic & Physical Chemistry, CSIR-Indian
Institute of Chemical Technology, Uppal Road, Tarnaka, Hyderabad 500007, Telangana, India
| | - P. Padmaja
- Department
of Chemistry, Faculty of Science, M. S.
University of Baroda, Sayajigunj, Vadodara 390002, Gujarat, India
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Shaida MA, Dutta R, Sen A. Removal of diethyl phthalate via adsorption on mineral rich waste coal modified with chitosan. J Mol Liq 2018. [DOI: 10.1016/j.molliq.2018.04.031] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Das S, Samanta A, Gangopadhyay G, Jana S. Clay-Based Nanocomposites as Recyclable Adsorbent toward Hg(II) Capture: Experimental and Theoretical Understanding. ACS OMEGA 2018; 3:6283-6292. [PMID: 31458810 PMCID: PMC6644673 DOI: 10.1021/acsomega.8b00789] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/23/2018] [Accepted: 05/23/2018] [Indexed: 05/26/2023]
Abstract
Here, we report the development of inorganic-organic hybrid nanocomposites through selective modification of the negative outer surfaces of halloysite nanoclays with two different organosilanes having primary or secondary amine sites to be explored them as novel and cost-effective adsorbents for the extraction of toxic inorganic contaminants from aqueous solution. They possess excellent selectivity for the adsorption of mercury, which shows monolayer molecular adsorption over the nanocomposites. The adsorption kinetics of Hg(II) is very fast and follows pseudo-second-order model compared to pseudo-first-order model. A combined experimental and theoretical study demonstrated that Hg(II) uptake by these nanocomposites is highly favorable and spontaneous up to 40 °C, and beyond this temperature, the uptake capacity gradually reduced. Temperature-dependent adsorption study exhibits endothermicity at low temperature (≤40 °C) and exothermicity beyond 40 °C. pH-dependent adsorption study showed their high uptake capacity until pH 7, which reduced at alkaline pH. All of the nanocomposites hold excellent adsorption capacity even at low concentration of adsorbate, along with multicycle sorption capability. The outstanding adsorption capacity as well as the easy synthetic route to achieve these nanocomposites may attract researchers to develop low-cost adsorbents to capture toxic metals, which in turn regulate the permissible limit of these toxic metals in drinking water.
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Affiliation(s)
- Sankar Das
- Department
of Chemical, Biological & Macro-Molecular Sciences and Technical Research
Centre, S. N. Bose National Centre for Basic
Sciences, Block-JD, Sector-III, Salt Lake, Kolkata 700106, India
| | - Arnab Samanta
- Department
of Chemical, Biological & Macro-Molecular Sciences and Technical Research
Centre, S. N. Bose National Centre for Basic
Sciences, Block-JD, Sector-III, Salt Lake, Kolkata 700106, India
| | - Gautam Gangopadhyay
- Department
of Chemical, Biological & Macro-Molecular Sciences and Technical Research
Centre, S. N. Bose National Centre for Basic
Sciences, Block-JD, Sector-III, Salt Lake, Kolkata 700106, India
| | - Subhra Jana
- Department
of Chemical, Biological & Macro-Molecular Sciences and Technical Research
Centre, S. N. Bose National Centre for Basic
Sciences, Block-JD, Sector-III, Salt Lake, Kolkata 700106, India
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Safari M, Shahlaei M, Yamini Y, Shakorian M, Arkan E. Magnetic framework composite as sorbent for magnetic solid phase extraction coupled with high performance liquid chromatography for simultaneous extraction and determination of tricyclic antidepressants. Anal Chim Acta 2018; 1034:204-213. [PMID: 30193635 DOI: 10.1016/j.aca.2018.06.023] [Citation(s) in RCA: 65] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2018] [Revised: 06/03/2018] [Accepted: 06/08/2018] [Indexed: 01/15/2023]
Abstract
In this study, magnetic framework composites (MFCs) (Fe3O4@TMU-10) microspheres were successfully fabricated and applied as an effective sorbent for preconcentration of the two model tricyclic antidepressants (TCAs) amitriptyline and imipramine from biological samples. MFCs were fabricated by a step-by-step assembly, novel, simple and efficient strategy. The shell thickness of the Metal-organic frameworks (MOFs) could also be easily controlled by tuning the number of assembly cycles. By coupling magnetic solid-phase extraction (MSPE) with high-performance liquid chromatography with UV detector (HPLC-UV), a simple, reliable, fast, sensitive and cost-effective method for simultaneous determination of TCAs was developed. Under optimal conditions, the preconcentration factors and relative recoveries of the studied compounds were obtained in the range of 43-50 and 90.5-99.0% respectively. The calibration curves were obtained in the range of 5-800 μg L-1 with reasonable linearity (R2 > 0.9904) and the limits of detection (LODs) ranged between 2 and 4 μg L-1 (based on S/N = 3). The relative standard deviations of intra- and inter-day tests ranged from 3.1 to 4.6% and from 4.3 to 5.2%, respectively. The results demonstrate that Fe3O4@TMU-10 core-shell magnetic microspheres combine advantages of MOFs and magnetic nanoparticles, and are the promising sorbents for rapid and efficient extraction of target analytes from urine and plasma complex biological samples.
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Affiliation(s)
- Meysam Safari
- Pharmaceutical Sciences Research Center, Faculty of Pharmacy, Kermanshah University of Medical Sciences, Kermanshah, Iran
| | - Mohsen Shahlaei
- Nano Drug Delivery Research Center, Kermanshah University of Medical Sciences, Iran.
| | - Yadollah Yamini
- Department of Chemistry, Tarbiat Modares University, P.O. Box 14115-175, Tehran, Iran
| | - Mehrzad Shakorian
- Department of Chemistry, Tarbiat Modares University, P.O. Box 14115-175, Tehran, Iran
| | - Elham Arkan
- Pharmaceutical Sciences Research Center, Faculty of Pharmacy, Kermanshah University of Medical Sciences, Kermanshah, Iran
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11
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Cheng J, Wang X, Li Y, Ning P. Adsorption and Catalytic Oxidation of Mercury over MnOx/TiO2 under Low-Temperature Conditions. Ind Eng Chem Res 2017. [DOI: 10.1021/acs.iecr.7b02749] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Jinhuan Cheng
- Faculty of Environmental
Science and Engineering, Kunming University of Science and Technology, Kunming 650500, PR China
| | - Xueqian Wang
- Faculty of Environmental
Science and Engineering, Kunming University of Science and Technology, Kunming 650500, PR China
| | - Yanan Li
- Faculty of Environmental
Science and Engineering, Kunming University of Science and Technology, Kunming 650500, PR China
| | - Ping Ning
- Faculty of Environmental
Science and Engineering, Kunming University of Science and Technology, Kunming 650500, PR China
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12
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Wang L, Zhao Y, Zhang J. Comprehensive Evaluation of Mercury Photocatalytic Oxidation by Cerium-Based TiO2 Nanofibers. Ind Eng Chem Res 2017. [DOI: 10.1021/acs.iecr.6b04995] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Lulu Wang
- State Key Laboratory of Coal
Combustion, Huazhong University of Science and Technology, Wuhan 430074, P. R. China
| | - Yongchun Zhao
- State Key Laboratory of Coal
Combustion, Huazhong University of Science and Technology, Wuhan 430074, P. R. China
| | - Junying Zhang
- State Key Laboratory of Coal
Combustion, Huazhong University of Science and Technology, Wuhan 430074, P. R. China
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13
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14
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Shen B, Li Z, Chen J, Singh S, He C. Kinetics study on the capture of elemental mercury in flue gas by KI-impregnated clays. CAN J CHEM ENG 2015. [DOI: 10.1002/cjce.22284] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Boxiong Shen
- School of Energy & Environmental Engineering; Hebei University of Technology; Tianjin 300401 China
- College of Environmental Science & Engineering; Nankai University; Tianjin 300071 China
| | - Zhuo Li
- College of Environmental Science & Engineering; Nankai University; Tianjin 300071 China
| | - Jianhong Chen
- College of Environmental Science & Engineering; Nankai University; Tianjin 300071 China
| | - Surjit Singh
- Energy & Research Institute; The University of Leeds; Leeds LS2 9JT UK
| | - Chuan He
- College of Environmental Science & Engineering; Nankai University; Tianjin 300071 China
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15
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Wang XQ, Wang P, Ning P, Ma YX, Wang F, Guo XL, Lan Y. Adsorption of gaseous elemental mercury with activated carbon impregnated with ferric chloride. RSC Adv 2015. [DOI: 10.1039/c5ra01011j] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Fe-based modified activated carbon prepared by impregnation was used for adsorbents in Hg0 purification.
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Affiliation(s)
- Xue Qian Wang
- Kunming University of Science & Technology
- Kunming
- China
| | - Ping Wang
- Kunming University of Science & Technology
- Kunming
- China
| | - Ping Ning
- Kunming University of Science & Technology
- Kunming
- China
| | - Yi Xing Ma
- Kunming University of Science & Technology
- Kunming
- China
| | - Fei Wang
- Kunming University of Science & Technology
- Kunming
- China
| | - Xiao Long Guo
- Kunming University of Science & Technology
- Kunming
- China
| | - Yi Lan
- Kunming University of Science & Technology
- Kunming
- China
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16
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Balasundaram K, Sharma M. Investigations into a thiol-impregnated CaCO3-based adsorbent for mercury removal: a full factorial design approach. RSC Adv 2015. [DOI: 10.1039/c5ra10902g] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
We demonstrated removal of Hg0 vapor by adsorbing it on thiol-impregnated calcium carbonate and assessed the significance of temperature and thiol mass in Hg0 removal.
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Affiliation(s)
| | - Mukesh Sharma
- Department of Civil Engineering
- Indian Institute of Technology Kanpur
- India
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17
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Wang Y, Liu Y, Mo J, Wu Z. Effects of Mg2+ on the bivalent mercury reduction behaviors in simulated wet FGD absorbents. JOURNAL OF HAZARDOUS MATERIALS 2012; 237-238:256-261. [PMID: 22981742 DOI: 10.1016/j.jhazmat.2012.08.036] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/02/2012] [Revised: 07/18/2012] [Accepted: 08/16/2012] [Indexed: 06/01/2023]
Abstract
This paper studied the bivalent mercury reduction behaviors after Mg(2+) addition in the simulated Ca-based and Dual-Alkali flue gas desulfurization (FGD) absorbents. Experimental results showed that the reduction of bivalent mercury was increased in the Ca-based FGD absorbent and inhibited in the Dual-Alkali FGD absorbent. It was proposed that the former was mainly attributed to the enhanced dissolution and recrystallization of CaSO(3) particles by Mg(2+) addition, which provided more active surface for mercury adsorption and reduction, whilst the latter was mainly due to the formation of neutral MgSO(3)(0) ion pair, which tended to lower the active sulfite concentration in the simulated solution.
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Affiliation(s)
- Yuejun Wang
- Zhejiang Provincial Engineering Research Center of Industrial Boiler & Furnace Flue Gas Pollution Control, Hangzhou 310027, PR China
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Adsorption of mercury(II), methyl mercury(II) and phenyl mercury(II) on chitosan cross-linked with a barbital derivative. Carbohydr Polym 2011. [DOI: 10.1016/j.carbpol.2011.06.028] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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Zhao P, Guo X, Zheng C. Removal of elemental mercury by iodine-modified rice husk ash sorbents. J Environ Sci (China) 2010; 22:1629-1636. [PMID: 21235196 DOI: 10.1016/s1001-0742(09)60299-0] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Iodine-modified calcium-based rice husk ash sorbents (I2/CaO/RHA) were synthesized and characterized by X-ray diffraction, X-ray fluorescence, and N2 isotherm adsorption/desorption. Adsorption experiments of vapor-phase elemental mercury (Hg0) were performed in a laboratory-scale fixed-bed reactor. I2/CaO/RHA performances on Hg0 adsorption were compared with those of modified Ca-based fly ash sorbents (I2/CaO/FA) and modified fly ash sorbents (I2/FA). Effects of oxidant loading, supports, pore size distribution, iodine impregnation modes, and temperature were investigated as well to understand the mechanism in capturing Hg0. The modified sorbents exhibited reasonable efficiency for Hg0 removal under simulated flue gas. The surface area, pore size distribution, and iodine impregnation modes of the sorbents did not produce a strong effect on Hg0 capture efficiency, while fair correlation was observed between Hg0 uptake capacity and iodine concentration. Therefore, the content of I2 impregnated on the sorbents was identified as the most important factor influencing the capacity of these sorbents for Hg0 uptake. Increasing temperature in the range of 80-140 degrees C caused a rise in Hg0 removal. A reaction mechanism that may explain the experimental results was presumed based on the characterizations and adsorption study.
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Affiliation(s)
- Pengfei Zhao
- State Key Laboratory of Coal Combustion, Huazhong University of Science and Technology, Wuhan 430074, China.
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ZHANG AC, SUN LS, XIANG J, HU S, FU P, Su S, ZHOU YB. Removal of elemental mercury from coal combustion flue gas by bentonite-chitosan and their modifier. ACTA ACUST UNITED AC 2009. [DOI: 10.1016/s1872-5813(10)60005-9] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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