• 대한화학회지
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• 제55권3호
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• pp.454-462
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• 2011

C-Metylcalix[4]resorcinarene(CMCR)에서 Pb(II)와 Cr(III)의 흡착 특징에 대한 연구는 수행되어왔다. CMCR은 resorcinol, acetaldehyde 그리고 HCl로 부터 1단계 합성으로 만들어졌다. 일괄처리시스템에서 대부분의 변수는 CMCR이 Pb(II)와 Cr(III)에 대해 좋은 흡착제라는 것을 확인했다. Cr(III)은 Pb(II)보다 더 크게 흡착되지만 Cr(III)의 흡착속도는 Pb(II) 보다 더 느리다. Pb(II)와 Cr(III) 흡착의 흡착운동에너지는 batch안에서 유사 2차 운동 모델을 따른다. 그러나 고정상 컬럼 시스템에서 Pb(II)의 운동에너지는 일차 모델을 따른다. 흡착된 Pb(II)을 되찾기 위한 탈착 연구는 증류수와 HCl을 가지고 순차적으로 수행되었다. 그리고 그 결과는 흡착은 화학흡착에 의해 지배된다는 것을 보여주었다.

• Biotechnology and Bioprocess Engineering:BBE
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• 제10권3호
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• pp.280-283
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• 2005

The adsorption of a model protein bovine serum albumin (BSA) in expanded bed chromatography was undertaken by exploiting a commercially available expanded bed column (20 mm i.d.) from UpFront Chromatography and Streamline DEAE $(\rho=1.2g/cm^3)$ from Amersham Pharmacia Biotechnology. The influence of whole yeast cells on the adsorption capacity of column was explored by employing yeast cells in a concentration ranged of 0 to $15\%(w/v)$. Equilibrium isotherms for adsorption of BSA on Streamline DEAE were correlated by using Langmuir equation. The presence of yeast cells resulted in decreased of BSA binding capacity in both batch binding and expanded bed chromatography. Results indicated that the yeast cells act as competitor for proteins to bind to the sites on adsorbents.

• Journal of Ginseng Research
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• 제22권3호
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• pp.155-160
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• 1998

This stuffy was carried to establish a new efficient method for the preparation of edible crude ginseng saponin. The conventional butanol extraction and resin adsorption methods were compared for the contents of total crude ginseng saponin and major ginsenosides. Seventy- percent methanol extract was applied to Diaion HP-20 column and the resin was washed with Hn and eluted with absolute methanol. The methanol elute was dried in vivo and analyzed for its ginsenosides. Use of ethanol instead of methanol to make edible crude ginseng saponin gave a similar result. Butanol extraction was performed by the conventional method. The final aqueous layer from butanol extraction was passed through Diaion HP-20 column followed by elution with methanol and Diaion HP-20 passed fraction was extracted with butanol to recover remaining components, respectively, in order to determine saponin loss. TLC and HPLC qualitatively and quantitatively monitored Ginsenosides, respectively. Loss of ginsenosides was higher in butanol extraction method than in Diction HP-20 adsorption method. In addition, saponin fractions prepared by Diction HP-20 adsorption method showed higher content of each ginsenoside, showing 8.2% higher purity than that of butanol extracted fraction. From these results, we propose the resin adsorption method as a new efficient measure for the preparation of crude ginseng saponin, which is edible by using spirit instead of methanol.

• Carbon letters
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• 제19권
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• pp.12-22
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• 2016

Date palm leaflets were used as a precursor to prepare dehydrated carbon (DC) via phosphoric acid treatment at 150℃. DC, acidified with H₃PO₄, was converted to activated carbon (AC) at 500℃ under a nitrogen atmosphere. DC shows very low surface area (6.1 m²/g) while AC possesses very high surface area (829 m²/g). The removal of lisinopril (LIS) and chlorpheniramine (CP) from an aqueous solution was tested at different pH, contact time, concentration, and temperature on both carbons. The optimal initial pH for LIS removal was 4.0 and 5.0 for DC and AC, respectively. However, for CP, initial pH 9.0 showed maximum adsorption on both carbons. Adsorption kinetics showed faster removal on AC than DC with adsorption data closely following the pseudo second order kinetic model. Adsorption increases with temperature (25℃–45℃) and activation energy (E_a) is in a range of 19–25 kJ mol/L. Equilibrium studies show higher adsorption on AC than DC. Thermodynamic parameters show that drug removal is endothermic and spontaneous with physical adsorption dominating the adsorption process. Column adsorption data show good fitting to the Thomas model. Despite its very low surface area, DC shows ~70% of AC drug adsorption capacity in addition of being inexpensive and easily prepared.

• 한국대기환경학회지
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• 제14권2호
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• pp.133-142
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• 1998

Gas adsorption on adsorbents depends on temperatures and pressures. When these parameters are fixed, the adsorption capability and selectivity can not be changed. If the gas adsorption is controlled by another factor like electromagnetic field, the adsorption and desorption can be managed by much intentional way. The microwave has characteristics to excite particular components such as water without destroying it. In this study, microwave was irradiated to the adsorbent of an NaY zeolite which is almost transparent to microwave. As vapor of 1, 1, 2- trichloro-1, 2, 2-trifluoroethane (CFC-113) and water flowed simultaneously on the zeolite packed in a column at room temperature, only water was adsorbed. The . adsorbed water was removed from the zeolite and then replaced by CFC-113, since the microwave was irradiated. Greater the power of microwave was, more CFC-113 was adsorbed. The water adsorption took place again after a latent period by stopping the microwave irradiation.

• 한국안전학회지
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• 제15권4호
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• pp.88-94
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• 2000

The adsorption characteristics of Tharonil on granular activated carbon were experimentally investigated in an adsorber and in a packed column. It was estabilished that the adsorption equilibrium of Tharonil on granular activated carbon was more successfully fitted by Freundlich isotherm equation than Langmuir isotherm equation in the concentration range from 1 to 1000 mg/1. Intraparticle diffusivities (pore and surface diffusivity) of Tharonil were estimated by the concentration-time curve and adsorption isotherm. The estimated values of pore diffusivity and surface diffusivity are $6.70{\times}10^{-6}$ and $2.0{\times}10^{-9}cm^2/s$, respectively. From comparison of intraparticle diffusivities, it was found that surface diffusion was the limiting step for adsorption rate. The break time and breakthrough curve predicted by constant pattern-linear driving force model were shown to agree with the experimental results.

• Advances in environmental research
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• 제3권3호
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• pp.231-251
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• 2014

The present study examines the phosphate adsorption potential and behavior of mixture of Ground Burnt Patties (GBP), a solid waste generated from cooking fuel used in earthen stoves and Red Soil (RS), a natural substance in fixed bed column mode operation. The characterization of adsorbent was done by Proton Induced X-ray Emission (PIXE), and Proton Induced ${\gamma}$-ray Emission (PIGE) methods. The FTIR spectroscopy of spent adsorbent reveals the presence of absorbance peak at $1127cm^{-1}$ which appears due to P = O stretching, thus confirming phosphate adsorption. The effects of bed height (10, 15 and 20 cm), flow rate (2.5, 5 and 7.5 mL/min) and initial phosphate concentration (5 and 15 mg/L) on breakthrough curves were explored. Both the breakthrough and exhaustion time increased with increase in bed depth, decrease in flow rate and influent concentration. Thomas model, Yoon-Nelson model and Modified Dose Response model were used to fit the column adsorption data using nonlinear regression analysis while Bed Depth Service Time model followed linear regression analysis under different experimental condition to evaluate model parameters that are useful in scale up of the process. The values of correlation coefficient ($R^2$) and the Sum of Square Error (SSE) revealed the Modified Dose Response model as the best fitted model to the experimental data. The adsorbent mixture responded effectively to the desorption and reusability experiment. The results of this finding advocated that mixture of GBP and RS can be used as a low cost, highly efficient adsorbent for phosphate removal from aqueous solution.

• 폴리머
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• 제26권4호
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• pp.516-522
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• 2002

4급 암모늄기를 관능기로 갖는 아민화 아크릴계 이온교환섬유를 이용하여 연속식 흡착공정 중 linear alkylbenzene sulfonate(LAS)의 흡착특성을 확인하였다. 아민화 아크릴계 이온교환섬유의 LAS흡착성능은 온도가 증가함에 따라 증가하였으며 $40^{\circ}C$에서 최적 흡착성능을 나타내었다. 또한 컬럼 베드 충진비(L/D)의 변화에 따른 LAS 이온의 흡착능은 L/D>2에서 최대 흡착능을 나타내었다. pH 변화에 따른 LAS이온 흡착능은 pH가 증가함에 따라 증가하는 경향을 나타내었고, pH 7에서 최대 흡착능을 나타내었다. 유속변화에 따른 LAS 흡착능은 유속이 증가할수록 낮아졌으며 농도가 높을수록 떨어졌다.

• 한국식품과학회지
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• 제29권2호
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• pp.204-210
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• 1997

소나무(Pinus densiflora Siebold et Zuccarini) 잎의 ethyl acetate 추출물은 세균, 효모, 곰팡이에 대하여 항미생물활성을 나타내었다. 활성물질을 solvent fractionation, silica gel adsorption column chromatography, Sephadex LH-20 column chromatography 등에 의해 정제하여 백색결정상 물질로 단리하였다. $MS,\;^{1}H-NMR,\;^{13}C-NMR$ 등의 기기분석에 의해 단리된 물질의 구조해석을 시도한 결과 benzoic acid로 동정되었다. Benzoic acid가 솔잎에서 분리, 동정된 것은 처음으로 생각되며 특히, 솔잎 생체중량 g당 0.608 mg이나 함유되어 있어, 타 식물체에 비하여 대단히 많은 양이 함유되어 있음이 확인되었다.

• 한국미생물·생명공학회지
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• 제28권2호
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• pp.92-96
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• 2000

통풍과 oxygen free radical의 독성에 관여하는 xanthine oxidase에 대한 새로운 저해물질의 탐색 및 개발을 목적으로 본 연구에서 선택분리한 Aspergillus sp. F184가 생산하는 저해물질을 분리.정제하고 구조를 결정하였으며 효소저해활성을 조사하였다. 본 균주를 배양 후 배양액을 여과하여 균체와 배양액을 분리하고 균체를 acetone으로 추출하고 감압농축하고 남은 수용액층을 배양액과 합쳐 HP-20 adsorption column chromatography, ethyl acetate 추출, silica gel column chromatography, 결정화 등을 실시하여 xanthine oxidase에 대한 저해물질을 분리, 정제하였다. 본 저해물질의 구조를 NMR 및 MS 스펙트럼을 측정하여 분석한 결과 5,6-epoxy-2-hydroxy-3-methyl-2-cyclohexene-1,4-dione으로서 terreic acid로 동정되었다. Terreic acid의 xanthine oxidase에 대한 저해활성을 조사한 결과 IC50가 1.1$\times$10-7M로서 기존의 저해제인 allopurinol과 유사하였다. 이에 terreic acid에 의한 xanthine oxidase 저해활성은 보고된 바가 없기에 새로운 통풍치료제로서의 가능성이 있음을 보고한다.