• 한국신재생에너지학회:학술대회논문집
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• 2011.05a
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• pp.221.1-221.1
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• 2011

In this study, we prepared the nitrogen-containing carbon spheres with mesopore processed by a facile polymerization-induced colloid aggregation method including carbonization in order to investigate the characterization and the effect on their carbon dioxide adsorption behaviors. The carbonization temperature was varied in the range of $600^{\circ}C$ to $900^{\circ}C$. The nitrogen contents of the mesoporous carbon sphere were characterized using XPS. The carbon dioxide adsorption capacities of the prepared mesoporous carbon sphere were determined by the amounts of carbon dioxide adsorptions at 298 K and 1.0 atm. The results showed that the prepared mesoporous carbons were highly effective for the carbon dioxide adsorption due to the increasing the affinity of the basic functionalities of adsorbent surface to acidic carbon dioxide. Maximum adsorption capacities of carbon dioxide at $25^{\circ}C$ were achieved up to 106 mg/g.

• Bulletin of the Korean Chemical Society
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• v.32 no.9
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• pp.3377-3381
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• 2011

In this work, the amine grafting treated activated carbons were studied for carbon dioxide adsorbent. The surfaces of activated carbon were functionalized by 3-chloropropyltrimethoxysilane, which was subsequently grafted with amine compounds tris-(2-aminoethyl)amine and tri-ethylenetetramine and subjected to comparison. The surface functional groups of the amine grafted activated carbons were characterized using XPS. The textural properties of the amine grafted activated carbons were analyzed by $N_2$/77 K isotherms. Carbon dioxide adsorption behaviors of the amine grafted activated carbons were examined via the amounts of carbon dioxide adsorption at 298 K and 1.0 atm. From the results, tris-(2-aminoethyl)amine grafted activated carbons showed 43.8 $cm^3$/g of carbon dioxide adsorption while non-treated activated carbons and triethylenetetramine grafted activated carbons showed less carbon dioxide adsorption. These results were thought to be due to the presence of isolated amine groups in the amine compounds. Tris-(2-aminoethyl)amine grafted activated carbons have basic features that result in the enhancement of adsorption capacity of the carbon dioxide molecules, which have an acidic feature.

• 한국신재생에너지학회:학술대회논문집
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• 2011.05a
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• pp.221.2-221.2
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• 2011

In this study, we prepared the magnesium oxide decorated ordered mesoporous carbons processed by the reduction of magnesium oxide precursor on the CMK-3 surfaces in order to investigate the characterization and the effect on their carbon dioxide adsorption behaviors. The magnesium contents of the prepared samples were characterized using XPS. The textural properties of the prepared samples were investigated by $N_2$/77 K adsorption isotherms by BET equation. The carbon dioxide adsorption capacities of the prepared samples were investigated by the amounts of carbon dioxide adsorptions at 298 K and 1.0 atm. The results showed that the magnesium oxide on the CMK-3 surface enhanced interaction between carbon dioxide and adsorbents. Consequently, it was found that the magnesium oxide led to an increase in the carbon dioxide adsorption capacity of the CMK-3.

• The Journal of Engineering Research
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• v.6 no.2
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• pp.85-98
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• 2004

The adsorption equilibrium data for the binary gas mixture system from the pure gas adsorption data of carbon dioxide and ethylene on ZSM-5 prepared were predicted. The binary gas mixture adsorption data have been examined against predicted values by two models-the vacancy solution model(VSM) and the statistical thermodynamic model(STM), using parameters obtained from the single component isotherm. The binary gas mixture data for the carbon dioxide-ethylene system were obtained for cation exchanged forms of ZSM-5 for the gas phase carbon dioxide mole fraction of 0.752 at $37^{\circ}C$ and 1 atm. The experimental adsorption phase diagrams were obtained for carbon dioxide-ethylene on sodium form ZSM-5 synthesized. The single component adsorption isotherms for carbon dioxide and ethylene were also obtained for this zeolite. The single component data were used to obtain parameters derived in two models. These parameters were, in turn, used to predict the binary mixture isotherms for this zeolite. Both the vacancy solution and the statistical thermodynamic models give satisfactory predictions of adsorption phase diagrams for the binary gas mixtures of carbon dioxide and ethylene on sodium exchanged ZSM-5. Also the correlation between the experimental data and the predicted values is generally in good agreement. The system appears to show ideal behavior with a relatively constant separation factor. The slight increase in adsorption capacity with an increase in ionic radius is due, in part, to the higher polarizability associated with larger cations.

• Journal of Korean Society for Atmospheric Environment
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• v.27 no.2
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• pp.191-200
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• 2011

A way to adsorptively remove indoor carbon dioxide at relatively lower concentration under ambient temperature was studied. A small lab-scale carbon dioxide adsorption and desorption reactors were prepared, and 5A and 13X zeolites were packed in this reactors to investigate their adsorption and desorption characteristics. The inflow carbon dioxide concentration was controlled to 5,000 ppm, relatively higher concentration found in indoor spaces with air quality problems, by diluting carbon dioxide with nitrogen gas. The flow rate was varied as 1~5 L/min, and the carbon dioxide concentration after this reactor was constantly monitored to examine the adsorption characteristics. It was found that 5A adsorbed more carbon dioxide than 13X. A lab-scale carbon dioxide desorption reactor was also prepared to investigate the desorption characteristics of zeolites, which is essential for the regeneration of used zeolites. The desorption temperature was varied as $25{\sim}200^{\circ}C$, and the desorption pressure was varied as 0.1~1.0 bar. Carbon dioxide desorbed better at higher temperature, and lower pressure. 5A could be regenerated more than three times by thermal desorption at $180^{\circ}C$. It is required to modify zeolites for higher adsorption and better regeneration performances.

• Clean Technology
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• v.30 no.3
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• pp.248-257
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• 2024

Carbon dioxide is an undesired component of biogas and landfill gas. As a result, it needs to be removed from these mixtures in order to increase their heating value and reduce corrosion during treatment. Zeolites are a class of microporous materials that can be used as adsorbents for the separation of carbon dioxide from gas mixtures. In this work, the pure gas adsorption isotherms of methane and carbon dioxide and the selectivity of their mixture onto LTA-4A, FAU-13X and FAU-NaY adsorbents at temperatures of 273, 298 and 323 K and pressures up to 30 bars were calculated by the Monte Carlo method. Also, the influence of a flexible framework in a set of zeolites on the separation of methane and carbon dioxide was studied. Carbon dioxide adsorption onto the zeolites used in this work was more favorable than methane adsorption. The FAU-13X adsorbent had the highest adsorption capacity among the studied adsorbents. However, the selectivity of carbon dioxide over methane for LTA-4A was the highest. The adsorption capacities of a rigid framework were higher than those of a flexible framework. The influence of the framework flexibility in FAU on adsorption capacity was small. In contrast, its influence on selectivity seemed to be much larger.

• Applied Chemistry for Engineering
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• v.18 no.3
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• pp.273-278
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• 2007

The honeycomb adsorbents and adsorption process for carbon dioxide removal from fuel gas were investigated. Zeolite paper was made with Na-X zeolite powder and ceramic fiber as raw materials. $Li^+$, $Ca^{2+}$ or $K^+$ ion exchanges for Na-X zeolite and additional Na-X coating were performed on zeolite paper for increasing the carbon dioxide adsorption capacity, after that the adsorption characteristics of the samples were analyzed. Among the ion exchanged samples, $Li^+$ ion exchanged zeolite paper was most promising but its carbon dioxide adsorption capacity was less than expected for process application. However, additional Na-X coating was found to be an effective method for increasing the carbon dioxide adsorption capacity of the zeolite paper for process application. The carbon dioxide breakthrough test of the honeycomb adsorbent prepared with the zeolite paper was studied, and fuel gas treatment capacity was calculated when the honeycomb adsorbent was used in the rotary adsorption process.

• Journal of the Architectural Institute of Korea Structure & Construction
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• v.34 no.3
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• pp.37-42
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• 2018

The use of fly ash in construction materials is increasing worldwide due the various advantages of using it, such as to produce durable concrete, or to use less cement and thus lower carbon dioxide emissions. The quality of fly ash is often determined by loss on ignition value (LOI), where an upper limit of LOI is set in each country for quality control purpose. However, due to many reasons, production of high LOI fly ash is increasing that cannot be utilized in concrete, ending up in landfill. In this study, the effect of fly ash use in cementitious materials on nitrogen oxides adsorption is examined. In particular, the effect of using high LOI, and thus high carbon content fly ash on nitrogen oxides adsorption is investigated. The results suggest that the higher carbon content fly ash is related to higher nitrogen dioxide adsorption, although normal fly ash was also more effective in nitrogen dioxide adsorption than ordinary portland cement. Also, higher replacement rate of up to 40% of fly ash is beneficial for nitrogen dioxide adsorption. These results demonstrate that high carbon fly ash can be used as construction materials in an environmentally friendly way where strength requirement is low and where nitrogen oxides emissions are high.

• 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.

• Clean Technology
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• v.24 no.4
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• pp.287-292
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• 2018

Effect of physical property of activated carbon on its carbon dioxide adsorption was investigated for the effective control of carbon dioxide. Pinewood sawdust and coal were used as raw materials of activated carbon. Specific surface area, micropore volume and mesopore volume of the prepared activated carbons were determined, respectively. The prepared activated carbons were analyzed for their adsorption capacity of carbon dioxide. The adsorption capacity was then presented with respect to the surface area, micropore volume and mesopore volume, respectively. As a result, the specific surface area and micropore volume of both pinewood and coal activated carbon were highly related to its carbon dioxide capacity. Its mesopore volume hardly affected its carbon dioxide capacity. Preparation of activated carbon with high specific surface area and micropore volume was found to be critical to the effective control of carbon dioxide.