• Journal of the Korean Crystal Growth and Crystal Technology
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• v.26 no.6
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• pp.238-242
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• 2016

The effect of the alkali, alkali earth metal elements on selective catalytic reduction(SCR) catalyst deactivation behavior were investigated in terms of microstructure, surface area, pore volume and De-NOx test. Poisoned SCR catalyst were manufactured by injection of $K_2CO_3$, $Na_2CO_3$, $Ca(CH_3COO)_2{\cdot}H_2O$, $C_4H_6MgO_4{\cdot}4H_2O$, $H_3PO_4$ solutions in the new SCR catalyst at $350^{\circ}C$ for 6 hours. New and poisoned catalysts surface were similar. But specific surface area, pore volume decrease from Na, Mg, K, Ca, P compared to new SCR catalyst. Especially, Na poisoned catalyst surface area and pore size extremely decreased by $10.20m^2/g$, $0.061cm^2/g$. De-NOx test results of new and poisoned catalysts at $150{\sim}450^{\circ}C$ indicated that alkali metal (K, Na) poisoned SCR catalysts have the lowest De-NOx efficiency, alkali earth metal poisoned SCR catalysts (Ca, Mg) De-NOx efficiency are higher than alkali metal poisoned SCR catalysts. P poisoned SCR catalyst De-NOx efficiency is similar new SCR catalyst. It were considered that physical deactivation of SCR catalyst was affected by SCR catalyst surface area and pore volume change.

• Analytical Science and Technology
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• v.6 no.5
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• pp.463-469
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• 1993

HDBPDA ion exchange resin, {(4, 5) : (13, 14)-Dibenzo-6, 9, 12-trioxa-3, 15, 21, -triazabicyclo [15. 3. 1]heneicosa-(1, 17, 19)(18, 20, 21) triene ion exchange resin : HDBPDA ion exchange resin} had a capacity of 3.8meq/g dry resin. The distribution coefficients of alkali and alkaline earth metal ions on HDBPDA and strongly acidic cation exchange resin, Dowex 50W-X8(200-400mesh) in water, and the various concentrations of hydrochloric acid were determined. Concentration of hydrochloric acid have almost not influenced on the distribution coefficients of alkali and alkaline earth metal ions for the HDBPDA ion exchange resin, but generally the distribution coefficient slightly increased with decreasing concentration of hydrochloric acid. The distribution coefficients of metal ions in water are larger than those in various hydrochloric acid concentration. The distribution coefficients of alkali and alkaline earth metal ions for the Dowex 50W-X8 ion exchange resin increased with decreasing hydrochloric acid concentration. Especially, the distribution coefficients of alkaline earth metal ions increased rapidly compared to those for alkali metal ions. The distribution coefficients of alkali and alkaline earth metal ions on HDBPDA ion exchange resin increased in a linear manner with decreasing acid concentration, and the slope, d log Kd/d log $M_{HCl}$ is about -0.2. Of the distribution cofficients of alkali metal ions on Dowex 50W-X8, at range of moderate hydrochloric acid concentration, the slope is about -1, while the slope for alkaline earth metal ions is about -2. However, at very low hydrochloric acid concentration, the linear variation between distribution coefficient and acid concentration was not occurred, but the slope was deviated from above values at low acid concentration.

• Analytical Science and Technology
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• v.10 no.1
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• pp.60-65
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• 1997

Solvent extraction of alkali metal and alkaline earth metal cations by mono-crown ether(benzo-15-crown-5) and bis-(crown ether)s(ethylenediamine bis(4'-formyl benzo-15-crown-5)) containing benzo-15-crown-5 moieties were investigated with water-chloroform system at $25^{\circ}C$. The order of the extraction equilibrium constants($K_e$) and the complexation constants($K_c$) for the alkali metal and alkaline earth metal cations with mono-crown ether and bis-(crown ether)s were Ca(II)>Na(I)>Sr(II)>K(I)>Mg(II)>Rb(I) and Sr(II)>Ca(II)>K(I)>Rb(I)>Mg(II)>Na(I) respectively. These results were explained in terms of the size effect of metal cation and electron density effect. Also, the bis-(crown ether)s was found to extract metal cations more effectively than the corresponding mono-crown ether.

• Bulletin of the Korean Chemical Society
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• v.32 no.11
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• pp.3855-3860
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• 2011

The competitive solvent extractions of alkali and alkaline earth metals by di-ionizable calix[4]arene nano-baskets were studied using nine conformers of calix[4]arene nano-baskets. The objective of this work is to assess the variation of macrocycle conformation, orientation and position of pendant moieties upon the extraction parameters (efficiency, selectivity and $pH_{1/2}$) of the complexes. The results revealed that alternation of ring conformation in calixarene scaffold affects the solvent extraction parameters towards alkali and alkaline earth metals, while changing the orientation of pendant moieties from ortho- to para- as well as cis- to trans-analogues depicted no changes in those extraction parameters.

• 한국정보디스플레이학회:학술대회논문집
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• 2007.08a
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• pp.332-335
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• 2007

Electron injection improvement in OLED organic layers can be obtained by their doping or using alkaline-earth or alkali metals as electron injection layers (EIL). Common handling problems can be solved by an innovative metal dispensing technology to ensure controlled and reliable metal layers for OLED. Thickness and deposition rate of EIL during the process have been explored to optimize device performances.

• 한국정보디스플레이학회:학술대회논문집
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• 2006.08a
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• pp.1763-1768
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• 2006

Low work function alkali metals and alkaline earths successfully lower the electron injection barrier and increase electron injection into the organic layer in OLED displays, but their implementation is not easy. AlkaMax technology can ensure the required metal evaporation rate in a fast, homogeneous and easily controllable way.

• Korean Chemical Engineering Research
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• v.54 no.5
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• pp.671-677
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• 2016

The impregnated alkali metal (Na, K), and the alkali earth metal (Ca, Mg) activated carbons were produced from the bamboo activated carbon by soaking method of alkali metals and alkali earth metals solution. The carbonization and activation of raw material was conducted at $900^{\circ}C$. The specific surface area and the pore size distribution of the prepared activated carbons were measured. Also, NO and activated carbon reaction were conducted in a thermogravimetric analyzer in order to use for de-NOx agents of the used activated carbon. Carbon-NO reactions were carried out in the nonisothermal condition (the reaction temperature $20{\sim}850^{\circ}C$, NO 1 kPa) and the isothermal condition (the reaction temperature 600, 650, 700, 750, 800, $850^{\circ}C$, NO 0.1~1.8 kPa). As results, the specific volume and the surface area of the impregnated alkali bamboo activated carbons were decreased with increasing amounts of the alkali. In the NO reaction, the reaction rate of the impregnated alkali bamboo activated carbons was promoted to compare with that of the bamboo activated carbon [BA] in the order of BA(Ca)> BA(Na)> BA(K)> BA(Mg) > BA. Measured the reaction orders of NO concentration and the activation energy were 0.76[BA], 0.63[BA(Na)], 0.77[BA(K)], 0.42[BA(Ca)], 0.30 [BA(Mg)], and 82.87 kJ/mol[BA], 37.85 kJ/mol[BA(Na)], 69.98 kJ/mol[BA(K)], 33.43 kJ/mol[BA(Ca)], 88.90 kJ/mol [BA(Mg)], respectively.

• Bulletin of the Korean Chemical Society
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• v.16 no.8
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• pp.716-720
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• 1995

• Journal of Korean Society of Water and Wastewater
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• v.30 no.6
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• pp.683-690
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• 2016

Modified coagulants were investigated for the removal of phosphorus from secondary effluent of wastewater treatment. The modified coagulants were prepared by mixing alkali earth metal ions such as calcium and magnesium. The basicity of a coagulant influenced on the removal of phosphorus, and coagulants with basicity of 5.9% showed a better removal of total phosphorus than that of 38.5%. Also, coagulants with alkali earth metals enhanced the performance of coagulation by 10% and resulted in 67.1% for total phosphorus removal. Moreover, the removal of suspended solids and chemical oxygen demand was improved using coagulants with low basicity and earth metal ions. Results of this study demonstrated that the use of coagulants with low basicity, and calcium and magnesium ions is recommended to improve wastewater effluent quality.

• Macromolecular Research
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• v.13 no.2
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• pp.141-146
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• 2005

Calix[4]crown-6-2,4-bis(4-aminobutyl ether), which has a crown-6 moiety at the 1,3-position and amino function at the 2,4-position, was prepared as an intermediate for the subsequent synthesis of calix[4]crown-6-containing polyamide and polyimide using adipoyl chloride and 1,2,4,5-benzenetetracarboxylic dianhydride. The chemical structures were characterized by IR, $^{1}H NMR$ spectroscopy and elemental analysis, and some of their physical properties, including their thermal behavior, were examined. The ion binding characteristics of the monomer and polymers for alkali metal and alkali earth metal ions were measured by liquid-liquid extraction from the aqueous phase into the organic phase. It has been observed that polyamide has a high binding ability towards various metal cations as compared to polyimide, which showed cesium ion selectivity.