• Carbon letters
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• v.15 no.4
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• pp.295-298
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• 2014

In this work, nanoporous carbons (NPCs) were prepared by the self-assembly of polymeric carbon precursors and block copolymer template in the presence of tetraethyl orthosilicate and colloidal silica. The NPCs' pore structures and total pore volumes were analyzed by reference to $N_2$/77 K adsorption isotherms. The porosity and elemental mercury adsorption of NPCs were increased by activation with carbon dioxide. It could be resulted that elemental mercury adsorption ability of NPCs depended on their specific surface area and micropore fraction.

• Bulletin of the Korean Chemical Society
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• v.32 no.4
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• pp.1321-1326
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• 2011

In this work, the effects of different surface functional groups on the elemental mercury adsorption of porous carbons modified by chemical treatments were investigated. The surface properties of the treated carbons were observed by Boehm's titration and X-ray photoelectron spectroscopy (XPS). It was found that the textural properties, including specific surface area and pore structures, slightly decreased after the treatments, while the oxygen content of the ACs was predominantly enhanced. Elemental mercury adsorption behaviors of the acidtreated ACs were found to be four or three times better than those of non-treated ACs or base-treated ACs, respectively. This result indicates that the different compositions of surface functional groups can lead to the high elemental mercury adsorption capacity of the ACs. In case of the acid-treated ACs, the $R_{C=O}/R_{C-O}$ and $R_{COOH}/R_{C-O}$ showed higher values than those of other samples, indicating that there is a considerable relationship between mercury adsorption and surface functional groups on the ACs.

• Clean Technology
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• v.19 no.4
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• pp.453-458
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• 2013

Fly ash has capacity to oxidize or adsorb mercury in a flue gas. Mercury oxidation and adsorption efficiencies of fly ash vary depending on the properties of fly ash. This study was designed to understand reaction characteristics of mercury with fly ash components. The fly ash components were tested to determine their oxidation and adsorption capabilities for elemental mercury and oxidized mercury. A sample was synthesized with fly ash components and tested. The test results were compared with those of the fly ash sample obtained from a coal-fired power plant. $Fe_2O_3$, CuO and carbon black showed higher oxidation or adsorption efficiency for elemental mercury while CaO, MgO, CuO and carbon black showed higher adsorption efficiency for mercury chloride. In addition, the synthesized sample showed comparable mercury oxidation and adsorption efficiencies to the fly ash sample.

• Composites Research
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• v.31 no.2
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• pp.76-81
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• 2018

In this study, the elemental mercury removal behaviors of silver-plated porous carbons materials were investigated. The pore structures and total pore volumes of the hybrid materials were analyzed by $N_2$ adsorption/desorption analysis at 77 K. The pore structures and surface morphologies of the hybrid materials were characterized by XRD and SEM, respectively. The elemental mercury adsorption capacities of all silver-plated porous carbons hybrid materials were higher than those of the as-received samples, despite the fact that the specific surface areas and total pore volumes decreased with increasing metal loading time. It was found that silver nanoparticles showed excellent elemental mercury removal behaviors in carbonaceous hybrid materials.

• Applied Biological Chemistry
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• v.41 no.4
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• pp.209-212
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• 1998

Methylan, a polysaccharide produced from Methylobacterium organophilum, was chemically modified by adding diethylaminoethyl (DEAE) group to the backbone of methylan. The structure of DEAE-methylan was determined by measuring its nitrogen content obtained from an elemental analysis. From the analysis of mass spectrum, the DEAE group in DEAE-methylan was also confirmed by determining diethylaminoethene as a separate form of DEAE. Mercury adsorption of DEAE-methylan was higher than that of native methylan. This fact was valid for a variety of pH, reaction times, metal concentrations, and polysaccharide concentrations. In particular, native methylan and DEAE-methylan adsorbed 16% (w/w) and 18% (w/w) for mercury after 30 min at pH 7, respectively. The increase in mercury adsorption of DEAE-methylan may be resulted from mercury adsorption by the lone pair electron of nitrogen atom in DEAE group.

• Journal of Korean Society for Atmospheric Environment
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• v.31 no.3
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• pp.302-314
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• 2015

There is an adsorption method using activated carbon as a typical method for removing elemental mercury. Physical characteristics of activated carbon such as specific surface area and volume of pore (micro and meso) have positive effect for mercury adsorption. Activated carbon is carbon-based material with a high specific surface area. This activated carbon can be manufactured through carbonization and activation process. In this process, physical characteristics of specific surface area and pore distribution are changed by controlling operating parameters like temperature, time and reagent of activation. In this study, we evaluated characteristics of activated carbons manufactured from pinewood and coal with the operating parameters. We evaluated mercury adsorption capacities of the activated carbons having excellent physical characteristics and compared those to the commercial activated carbon.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2004.05a
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• pp.241-242
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• 2004

• Journal of the Korea Academia-Industrial cooperation Society
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• v.22 no.5
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• pp.1-6
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• 2021

Mercury, once released, is not destroyed but accumulates and circulates in the natural environment, causing serious harm to ecosystems and human health. In the United States, sulfur-impregnated activated carbon is being considered for the removal of vapor mercury from the flue gas of coal-fired power plants, which accounts for about 32 % of the anthropogenic emissions of mercury. In this study, a high-efficiency porous mercury adsorption material was developed to reduce the mercury vapor in the exhaust gas of coal combustion facilities, and the mercury adsorption characteristics of the material were investigated. As a result of the investigation of the vapor mercury adsorption capacity at 30℃, the silica nanotube MCM-41 was only about 35 % compared to the activated carbon Darco FGD commercially used for mercury adsorption, but it increased to 133 % when impregnated with 1.5 % sulfur. In addition, the furnace fly ash recovered from the waste copper regeneration process showed an efficiency of 523 %. Furthermore, the adsorption capacity was investigated at temperatures of 30 ℃, 80 ℃, and 120 ℃, and the best adsorption performance was found to be 80 ℃. MCM-41 is a silica nanotube that can be reused many times due to its rigid structure and has additional advantages, including no possibility of fire due to the formation of hot spots, which is a concern when using activated carbon.

• Clean Technology
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• v.23 no.2
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• pp.172-180
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• 2017

Thermodynamic evaluation indicates that nearly 100% conversion of elemental mercury to oxidized mercury can be attained by HCl of several tens of ppm level at the temperature window of SCR reaction. Cu-, Fe-, Mn-chloride loaded $V_2O_5-WO_3/TiO_2$ catalysts revealed good NO removal activity at the operating temperature window of SCR process. The catalysts with high desorption temperature indicating adsorption strength of $NH_3$ revealed higher NO removal activity. The HCl fed to the reaction gases promoted the oxidation of mercury. However, the activity for the oxidation of elemental mercury to oxidized mercury by HCl was suppressed by $NH_3$ inhibiting the adsorption of HCl to catalyst surface under SCR reaction condition containing $NH_3$ for NO removal. Metal chloride loaded $V_2O_5-WO_3/TiO_2$ catalysts showed much higher activity for mercury oxidation than $V_2O_5-WO_3/TiO_2$ catalyst without metal chloride under SCR reaction condition. This is primarily attributed to the participation of chloride in metal chloride on the catalyst surface promoting the oxidation of elemental mercury.

• Journal of Soil and Groundwater Environment
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• v.25 no.1
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• pp.53-61
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• 2020

This study assessed the feasibility of coal mine drainage sludge (CMDS) as a stabilizing agent for mercury contaminated soil through pot experiments and batch tests. In the pot experiments with 43 days of lettuce growth, the bioavailability of mercury in the amended soil and mercury content of the lettuce were decreased by 46% and 50%, respectively. These results were similar to those of the soil amended with the sulfide compound (FeS) generally used for mercury stabilization. Thus, CMDS could be an attractive mercury stabilizer in terms of industrial by-product recycling. Batch tests were conducted to examine mercury fractionation including reactions between the soil and acetic acid. The result showed that some elemental fraction changed to strongly bounded fraction rather than residual (HgS) fraction. This made it possible to conclude that mercury adsorption on oxides in CMDS was the major mechanism of stabilization.