• KSBB Journal
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• 제23권1호
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• pp.31-36
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• 2008

The use of L-carbohydrates and their corresponding nucleosides in medicinal application has greatly increased. For example L-ribose has been much in demand as the starting material for curing hepatitis B. High performance liquid chromatography (HPLC) method was studied for the analysis of ribose and arabinose fractions from ion exchange chromatography (IEC). Dowex Monosphere 99 Ca/320 resin was packed in IEC to separate ribose and arabinose under various operating conditions. $NH_{2}$ and sugar HPLC columns were then used to analyze the fractions from the IEC column. Pulse input method (PIM) was also used to measure adsorption isotherms of ribose and arabinose in the Dowex column and HPLC columns. Experimental results and simulations by ASPEN chromatography were compared with fair agreement.

• 한국재료학회지
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• 제27권3호
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• pp.127-131
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• 2017

Isosteric heat of hydrogen adsorption is one of the most important parameters required to describe solid-state hydrogen storage systems. Typically, it is calculated from adsorption isotherms measured at 77K (liquid N2) and 87K (liquid Ar). This simple calculation, however, results in a high degree of uncertainty due to the small temperature range. Therefore, the original Sievert type setup is upgraded using a heating and cooling device to regulate the wide sample temperature. This upgraded setup allows a wide temperature range for isotherms (77K ~ 117K) providing a minimized uncertainty (error) of measurement for adsorption enthalpy calculation and yielding reliable results. To this end, we measure the isosteric heats of hydrogen adsorption of two prototypical samples: activated carbon and metal-organic frameworks (e.g. MIL-53), and compared the small temperature range (77~87K) to the wide one (77K ~ 117K).

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2003년도 총회 및 춘계학술발표회
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• pp.120-123
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• 2003

Immobilization behavior of methyl tert-butyl ether (MTBE) by various cyclodextrins(CDs) was studied to investigate the feasibility of MTBE removal using cyclodexrins. Even though MTBE has relatively low hydrophobicity and higher polarity compared to other organics, it was effectively immobilized by CDs. The immobilization isotherms was shown as a type of Freundlich isotherms, and the immobilization capacity of -CDs was the largest among natural COs. The initial apparent association constant for MTBE-CD complex follows the order : gamma = beta > methyl-beta > hydroxypropyl beta > alpha. These differences of the constants are related to the size of MTBE and CDs. The size of beta-CD and gamma-CD is large to encapsulate MTBE molecule into the cavity, which that of alpha-CB is too small to encapsulate MTBE.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2003년도 총회 및 춘계학술발표회
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• pp.201-204
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• 2003

Solubilization isotherms of 1-chlorobenzene (MCB) and 1, 2-dichlorobenzene (DCB) were investigated in ionic surfactant solutions such as sodium dodecyl sulfate (SDS), cetylpyridinium chloride (CPC), and dedecyltrimethylammonium chloride (DMAC). The solubilization extent of DCB was much higher than that of MCB because of the main driving force of solubilization Is hydrophobic interactions between chlorobenzenes and hydrophobic interior of ionic micelles and DCB is more hydrophobic than MCB. CPC showed highest solubilization capacity because of longest hydrophobic tails. Simultaneous solubilization of MCB and DCB decreased slightly the extent solubilization of both MCB and DCB because the solubilization locus in the micelles is same.

• Carbon letters
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• 제11권1호
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• pp.1-8
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• 2010

The adsorption of Acid Blue 92 onto three low cost and ecofriendly biosorbents viz., cow dung ash, mango stone ash and parthenium leaves ash and commercial activated carbon have discussed in this work. The ash of all the mentioned bio-wastes was prepared in the muffle furnace at $500^{\circ}C$ and all the adsorbents were stored in an air thermostat. Experiments at total dye concentrations of 10~100 mg/L were carried out with a synthetic effluent prepared in the laboratory. The parameters such as pH and dye concentration were varied. Equilibrium adsorption data followed both Langmuir and Freundlich isotherms. The results indicate that cow dung ash, mango stone ash and parthenium leaves ash could be employed as low-cost alternatives to commercial activated carbon in wastewater treatment for the removal of dye.

• Carbon letters
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• 제8권1호
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• pp.1-5
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• 2007

The use of low cost and ecofriendly adsorbent has been investigated as an alternative to the current expensive method of removing dyes from wastewater. Cow dung cakes were collected from the nearby village which was burnt in a muffle furnace at $500^{\circ}C$ to obtain the required ash. This paper deals with the removal of Reactive Blue 221, Acidoll Yellow 2GNL and Olive BGL which are mainly used in textile industry, from aqueous solution by cow dung ash without any pretreatment. The adsorption was achieved under different pH, adsorbate concentration and the applicability of Langmuir and Freundlich isotherms were examined.

• 약학회지
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• 제29권6호
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• pp.380-386
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• 1985

The adsorption of quinine, atropine and methylrozaniline chloride from aqueous phase by different kaolins was studied to innovated utilization of Korean kaolins as pharmaceutical agents. The adsorption isotherms were determined at $27{\pm}1^{\circ}C$ and the results were plotted according to the Langmuir equation. The Langmuir constants were calculated from adsorption isotherms of quinine and methylrozaniline chloride; a=1.46, 1.34 b=5.7, 9.3 and slope=0.175, 0.108, respectively. The kaolins gave the same type of curves with the two alkaloids and methylrozaniline chloride. The white colored premium grade kaolins were better adsorbent for the alkaloids and methylrozaniline chloride than the lower grade ones. The results indicate that the premium grade kaolins could be utilized as an ingredients in intestinal preparations. The condition of activation for the better adsorption was under the cases with the higher temperature and the lower pressure. The smaller particle size, the greater was adsorption power and the activated kaolins had superior adsorptive properties at higher pH value than at higher hydrogen-concentrations.

• 한국수소및신에너지학회논문집
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• 제16권4호
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• pp.307-314
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• 2005

In this work, a static volumetric method was experimentally implemented to measure the adsorption isotherm of hydrogen and methane by the activated carbon. The equilibrium data of stationary phase and mobile phase were correlated into the Langmuir, Freundlich, Langmuir-Freundlich, and Toth isotherms, respectively. In addition, the comparison between prediction and experimental data was made. By a nonlinear regression analysis, the experimental parameters in the equilibrium isotherms were estimated and compared. Then, the linear and quadratic equations for pressure and temperature to adsorption amounts were expressed. The adsorption amounts were increased with the pressure increase and the temperature decrease.

• 대한화학회지
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• 제18권2호
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• pp.79-84
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• 1974

진공미량저울을 써서 벤젠과 그 유도체들의 흑연화카아본블랙, Spheron6 위에서의 흡착등온 곡선을 얻었다. 이로부터 각 흡착질의 Spheron6 위에서의 분자단면적을 계산했다. 이 값들을 비교하여 흡착질이 Spheron6 표면에 흡착될 때, 벤젠고리는 흡착체 표면에 평행으로 되며 흡착질 분자는 이 평면 상에서 제한된 각도로 회전하고 있음을 밝혔다.

• 한국전자통신학회논문지
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• 제8권9호
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• pp.1365-1371
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• 2013

표면상에서의 흡착현상 중, 특정한 압력에서 흡착량이 불연속적으로 급격하게 증가하는 2상 공존현상을 이론적으로 설명하기 위하여 2차원 클러스트 응집모형을 도입하였다. 이 2차원 클러스트 응집모형에 기초적인 통계열역학과 미정계수법을 적용하여 흡착등온식을 유도하였으며, 유도된 흡착등온식은 표면흡착에서의 2상 공존현상이 흡착입자들 간의 강한 인력에 의한 것임을 정성적으로 잘 보여주었다.