• Title/Summary/Keyword: 알칼리 금속염

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A Study on the Sulfur-Resistant Catalysts for Water Gas Shift Reaction II. Effect of Alkali Metal Salt on the Activity of CoMo Catalyst (황에 저항성을 가지는 수성가스 전환반응 촉매의 연구 II. CoMo 촉매의 활성에 미치는 알칼리 금속염의 영향)

  • Kim, Joon Hee;Lee, Ho In
    • Journal of the Korean Chemical Society
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    • v.42 no.6
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    • pp.696-702
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    • 1998
  • The effect of alkali metal salt on the activity of Co-Mo catalyst which has high resistance to sulfur poisoning for water gas shift reaction(WGSR) was studied. Two groups of catalysts were prepared to investigate the effects of anion and cation in alkali metal salts. For K-doped catalysts made with various potassium salts having different anion, the catalytic activity was explained to depend mainly on the BET surface area. Among the catalysts prepared by various nitrates of alkali metal as precursor, the Li-doped catalyst showed the best activity, and the others did not make significant differences giving relatively low activities. And the change of BET surface area by varying the loading of alkali metal showed a similar trend to that of activity. In this case, the activity was dependent on both BET surface area and the ratio of $Mo^{6+}$ with a tetrahedral coordination symmetry to $Mo^{6+}$ with an octahedral one, $Mo^6+[T]/Mo^{6+}[O]$ value.

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CO2 Absorption by Alkali-modified Amino Acid Salts (알칼리금속을 함침시킨 아미노산 염 수용액의 이산화탄소 흡수특성 연구)

  • Lim, Yun-Hui;Jo, Young-Min;Park, Joon-Seok
    • Applied Chemistry for Engineering
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    • v.22 no.5
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    • pp.526-531
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    • 2011
  • The present study attempted to impregnate alkali metals to amino acid in order to improve $CO_2$ absorption capacity. A used amino acid was glycine, of which pH increased up to about 11 with the addition of alkalies. $CO_2$ absorption capacity of amino acid salts was evaluated in a batch and a continuous process. The absorption capacity appeared in turns as; Sodium Glycinate ${\geq}$ Lithium Glycinate > Potassium Glycinate. Amino acid salts showed lower absolute capacity of $CO_2$ absorption than primary amine (Monoethanolamine) at $20^{\circ}C$. In a continuous absorption with 10% $CO_2$ flow, the increasing the reaction temperature, the increasing rate of absorption for amino and was higher that of than amino absorbent.

Transient State Theory of Significant Liquid Structure Applied to Alkali Earth Chlorides (용융 알칼리토금속 염화물에 대한 천이상태 이론의 적용)

  • Ahn, Woon-Sun;Chang, Sei-Hun
    • Journal of the Korean Chemical Society
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    • v.14 no.1
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    • pp.109-112
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    • 1970
  • 액체구조의 천이상태 이론을 알칼리토금속 염화물에 적용시켜서 상태합을 유도하였다. 이 상태합으로부터 $SrCl_2$$BaCl_2$의 증기압, 몰부피, 엔트로피등의 열역학적 성질을 계산하여 실험치와 비교하였으며, 천이상태 이론이 용융염에도 잘 적용된다는 결론을 얻었다.

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Counterion Specific Conformational Transition and ion Selective Transport of a Poly(L-glutamic acid)/PVA Blend Membrane (Poly(L-glutamic acid)/PVA 블렌드막의 대이온 선택적인 구조전이와 이온투과 특성)

  • 허양일
    • Polymer(Korea)
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    • v.24 no.6
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    • pp.802-809
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    • 2000
  • Counterion-specific helix formation and ion-selective transport of alkali metal chlorides (LiCl, NaCl, KCl, CsCl) were investigated for a poly(L-glutamic acid)(PLGA)/poly (vinyl alcohol)(PVA) blend membrane immersed in aqueous ethanol. The counterion specificity for helix formation of PLG alkali metal salts in the membrane was Li>Na>K>Cs. This specificity is ascribed to a contact ion-pair formation between the PLG carboxyl anion and the bound counterion, which depends on the energy balance between the electrostatic interaction and the desolvation. In aqueous ethanol, an appreciable ion-selectivity was observed for the permeability coefficient, i.e. Li$^{+}{\cdot}$Cl$^{-}$) formation between counterion and coion, and the latter to a specific interaction of diffusing counterions with polymer charges.

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Synthesis of 2-Mercaptobenzoxazoles and 2-Mercaptobenzimidazole (2-Mercaptobenzoxazole 및 2-Mercaptobenzimidazole의 새로운 합성법)

  • Chung, Kun-Hoe;Lee, Dong-Guk;Ko, Young-Kwan;Ryu, Jae-Wook;Woo, Jae-Chun;Koo, Dong-Wan;Kim, Dae-Whang
    • The Korean Journal of Pesticide Science
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    • v.10 no.1
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    • pp.66-68
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    • 2006
  • New synthetic method of 2-mercaptobenzoxazoles and 2-mercaptobenzimidazoles was established using elemental sulfur, dichloromethane, inorganic base and catalysts in alcohol solvents. This reaction condition gave products in high yields.

Characterization of Glycine Metal Salts for $CO_2$ Absorption (이산화탄소 흡수를 위한 글리신 금속염의 특성 연구)

  • Lim, Yun-Hui;Park, Young Koo;Jo, Young-Min
    • Applied Chemistry for Engineering
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    • v.23 no.3
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    • pp.284-288
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    • 2012
  • This work deals with the chemical characterization of glycine aqueous solution in $CO_2$ absorption. Three alkali elements were impregnated into the glycine in order to facilitate the formation of amino functionalities. The analysis by IR revealed the transformation of ammonium ions to the amino group. In addition, the NMR analysis showed that the substitution of metal cations to the chemical shift of hydrogen and carbon atoms in glycine; in order of lithium glycinate, sodium glycinate and potassium glycinate depending on the electro negativity. Meanwhile, the $CO_2$ absorption at room temperature was the highest in primary amine solution, but at the increasing temperature sodium glycinate could capture more $CO_2$ than that of the pure amine solution.

Biogeochemistry of Alkaline and Alkaline Earth Elements in the Surface Sediment of the Gamak Bay (가막만 표층퇴적물 중 알칼리 및 알칼리 토금속 원소의 생지화학적 특성)

  • Kim, Pyoung-Joong;Park, Soung-Yun;Kim, Sang-Su;Jang, Su-Jeong;Jeon, Sang-Baek;Ju, Jae-Sik
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.18 no.1
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    • pp.1-13
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    • 2012
  • We measured various geochemical parameters, including the grain size, loss on ignition(LOI), total organic carbon(TOC), total nitrogen(TN), total sulfur(TS) and metallic elements, in surface sediment collected from 19 stations in Gamak Bay in April 2010 in order to understand the sedimentary types, the origin of organic matters, and the distribution patterns of alkali(Li, Na, K, Rb) and alkaline earth(Be, Mg, Ca, Sr, Ba) elements. The surface sediments were mainly composed of mud. The concentrations of Chlorophyll-a, TOC, TN, TS and LOI in sediment were the highest at the cultivation areas of fish and shellfish in the northern and southern parts of the bay. The redox potential(or oxidation-reduction potential) showed the positive value in the middle part of the bay, indicating that the surface sediment is under oxidized condition. The organic materials in sediment at almost all of stations were characterized by the autochthonous origin. Based on the overall distributions of metallic elements, it appears that the concentrations of alkali and alkaline earth elements except Ba in sediment are mainly influenced by the dilution effect of quartz. The concentrations of Sr and Ba are also dependent on the secondary factors such as the effect of calcium carbonate and the redox potential.

Adsorption Characteristics of CO2 on Activated Carbons Treated with Alkali-metal Salts (알칼리금속염으로 처리된 활성탄에 대한 CO2의 흡착특성)

  • Ryu, Dong Kwan;Kim, Sung Hyun
    • Applied Chemistry for Engineering
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    • v.9 no.2
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    • pp.286-293
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    • 1998
  • Two methods were used to enhance the adsorption capacity of activated carbons. One is to impregnate activated carbons with chemical compounds which have a good affinity for $CO_2$. The other is to activate by heat-treating after impregnation with KOH on activated carbons(AC). The chemical compounds impregnated on AC were alkali metal, alkaline earth metal, and transition metal chlorides. The adsorption capacity of $CO_2$ on AC impregnated with these metals was less than that of pure AC. These compounds have not the chemical affinity for $CO_2$ and obstruct the micropore of AC. The experiment of breakthrough for $CO_2$ on AC impregnated with KOH showed the increase of the adsorbed amount of $CO_2$ in influent gases containing water vapor. This means that KOH adsorbes $CO_2$ gas. However, the adsorbents impregnated with KOH had not the reproducibility because of the production of $K_2CO_3$ by the reaction of KOH with $CO_2$. The amount of $CO_2$ adsorbed on the heat-treated AC at $800^{\circ}C$ increased with the amount of impregnation. The adsorption capacity of $CO_2$ was the largest when the ratio of weight of KOH to AC equal to 4. The isosteric heat of adsorption was calculated by the equation of Clausius-Clapeyron form adsorption capacity data of $CO_2$ for the temperature change. In addition, the characteristics of $CO_2$ breakthrough curve were surveyed for the change of flow rate and concentration.

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