• Bulletin of the Korean Chemical Society
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• 제31권7호
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• pp.1945-1950
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• 2010

Solvent extraction experiments of Pt(IV), Pd(II) and Rh(III) by Alamine336 were performed from the mixed chloride solutions. In the HCl concentration range from 1 to 5 M, most of Pt and Pd were extracted from the mixed solutions. However, the extraction percentage of Rh was much smaller than that of Pt and Pd. Lower concentration of Alamine336 in strong HCl solution led to higher separation factor of Rh from Pt and Pd. Adding $SnCl_2$ to the mixed solutions increased the extraction percentage of Rh, while the extraction percentage of Pt and Pd was little affected. Our results showed that selective separation of Rh or coextraction of the three platinum group metals from the mixed solution would be possible by adjusting the extraction conditions.

• Nuclear Engineering and Technology
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• 제39권6호
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• pp.731-736
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• 2007

Radioactive organic wastes containing acetone, alcohol, and particularly tributyl phosphate (TBP)/dodecane contaminated with uranium are extracted from the PUREX process and the decontamination of related equipment. An evaporation method that utilizes existing DU oxidation apparatuses and ventilation systems and a typical muffle furnace installed with an aspirating system are adopted. A separation method using phosphoric acid especially for the TBP/dodecane waste is also studied and evaluated. The results show that a simple evaporation process is utilizable for wastes containing acetone or alcohol with a lower boiling point. A modified muffle furnace is more appropriate to dispose directly of organic wastes having a higher boiling point, such as TBP/dodecane, without generating a condensed waste solution. It is recommended that, when the uranium concentration of TBP/dodecane waste is much higher than stipulated levels, separation technology should be applied to remove uranium from the mixture. Each type of solvent after separation can then be considered disposable below the regulatory limit in the modified furnace discussed in this study.

• 한국막학회:학술대회논문집
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• 한국막학회 1999년도 The 7th Summer Workshop of the Membrane Society of Korea
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• pp.79-82
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• 1999

Using Small Angle Light Scattering (SALS), the effect of quench depth on the kinetics of phase separation for ternary solution blends was investigated. The system was composed of two polymers (polystyrene and polybutadiene) and a solvent (toluene). The analyses of the early stage of phase separation were based of the Cahn-Hilliard theory [1,5]. Apparent diffusion coefficients and the fastest mode of fluctuations were evaluated, when quench depth of the system were varied near the critical composition of polymer. In the late stage of phase separation, the domain growth showed a power law with the 1/3 exponent, i.e. $q_m(t)~t^{-1/3}$. For comparison between real images and scattering profiles with time, the image of phase domains with time were obtained by using Laser Confocal Scanning Microscopy (LSCM).

• 자원리싸이클링
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• 제24권5호
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• pp.56-62
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• 2015

폐 초내열합금으로부터 침출된 염산용액에서 레늄을 회수하기 위하여 용매추출법을 이용한 레늄의 분리연구를 수행하였다. 용매추출공정을 통해 수상은 레늄이 용해된 합성용액을 사용하고 추출제의 종류 및 농도, 수상의 pH, HCl의 농도, 불순물의 영향을 조사하는 연구를 진행하였다. 레늄의 원료로 Ammonium perrhenate ((APR), Aldrich, $NH_4ReO_4$)을 사용하였고, 수상에 존재하는 레늄을 유기상으로 추출하기 위해 추출제는 음이온추출제인 Alamine304-1, 양이온추출제인 Cyanex272과 $D_2EHPA$를 사용하였다. 음이온추출제인 Alamine304-1 사용시 레늄의 추출율이 99% 이상 나타났으며 수상의 pH 는 0-2 사이에서 99% 추출되었다. Alamine304-1의 농도를 0.1, 0.5, 1 및 2%으로 조절하여 추출실험한 결과, 농도가 증가함에 따라 추출율이 증가한다. 레늄용액에 알루미늄, 코발트, 바나듐을 첨가하여 용매추출법에 의해 분리 실험한 결과 레늄은 99.8 %으로 추출되었으나 기타 금속들은 거의 추출되지 않았다.

• 자원리싸이클링
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• 제12권1호
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• pp.25-32
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• 2003

도금폐수로부터 철, 구리, 아연 및 니켈 등 중금속을 분리ㆍ회수하기 위한 용매추출시 추출제의 종류 및 평형 pH에 따른 각 금속의 분리효과를 조사하였다. 실험결과 아연은 추출제로 PC-88A가 가장 효과적이며, pH 2.5에서 100% 추출할 수 있다. 구리와 니켈은 LIX 84를 사용하여 추출하면 각각 pH2에서 100% 그리고 pH4～5에서 90% 이상 추출할 수 있다. 한편, 중금속이 혼재한산ㆍ알칼리계 도금폐수에 대한 용매추출에서는 먼저 3가 철을 지방산인 20％의 Naphthenic acid나 10％의 Versatic acid-10로 pH2∼2.5 부근에서 분리ㆍ회수하고, 그 다음에 3%의 LIX 84를 사용하여 pH2에서 구리를 용매추출하여 분리하고 난 후 20% PC-88A 로 pH2.5∼3에서 아연을 용매추출하여 회수하면 수상에 니켈만이 잔류하여 각각의 금속분리가 가능하다.

• Journal of Radiation Protection and Research
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• 제28권1호
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• pp.25-33
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• 2003

악성 종양 진단에 사용되고 있는 방사성 동위원소 $^{67}Ga$의 대량생산을 위한 자동화장치를 개발하였다. $^{67}Ga$은 조사된 $^{68}Zn$ 농축타켓에서 분리 생산하며 생산방법으로는 크게 용매추출법과 이온수지 법이 이용된다. 분리과정을 자동화하기 위해서 전도도 측정 장치, 화학처리 초자, 에어 공급 및 용액공급튜브, 밸브들로 이루어진 분액장치와, 이 장치를 구동하고 제어하는 PLC 기반 콘트롤러 및 사용자 직접제어용 모니터링 장치로 구성된 시스템을 개발하였다. 개발된 시스템을 사용함으로써 생산 중에 발생되는 불필요한 방사선 피폭으로부터 생산자를 보호할 뿐만 아니라, 생산시간의 단축, 생산효율의 증대로 $^{67}Ga$ 대량 생산이 가능하게 되었다.

• 멤브레인
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• 제31권5호
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• pp.363-370
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• 2021

본 연구에서는 유기용매에 저항성이 뛰어난 소재인 polyketone 고분자를 사용하여 열유도 상분리법(TIPS)으로 유기용매 저항성 중공사 분리막을 제조하였다. 희석제는 green solvent로 알려진 PEG300, DMSO₂, glycerine을 사용하였으며, 이때 사용된 diluent에 따라 나타나는 구정형 구조를 가지는 고-액 상분리와 bicontinuous한 구조를 가지는 액-액 상분리를 관찰하였다. 전반적인 분리막의 특성은 SEM, 수투과도, 기계적 강도, 내화학실험을 사용하여 고찰하였으며, 본 연구에서는 다양한 희석제가 적용된 polyketone 중공사 분리막의 제조와 그 상호관계에 대해 심도 있게 연구하였다.

• Biotechnology and Bioprocess Engineering:BBE
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• 제11권4호
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• pp.293-298
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• 2006

A study on the feasibility of using improved computer-controlled HPLC and GC systems was carried out to shorten the time needed for measuring levels of the substrates (glucose, maltose, and glycerol) and products (acetone, butanol ethanol, acetic acid, and butyric acid) produced by Clostridium saccharobutylicum DSM 13864 during direct fermentation of sago starch to solvent. The use of HPLC system with a single injection to analyse the composition of culture broth (substrates and products) during solvent fermentation was achieved by raising the column temperature to $80^{\circ}C$. Although good separation of the components in the mixture was achieved, a slight overlap was observed in the peaks for butyric acid and acetone. The shape of the peak obtained and the analysis time of 26.66 min were satisfactory at a fixed flow rate of 0.8mL/min. An improved GC system was developed, that was able to measure the products of solvent fermentation (acetone, butanol, ethanol, acetic acid, and butyric acid) within 19.28 min. Excellent resolution for each peak was achieved by adjusting the oven temperature to $65^{\circ}C$.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2012년도 제42회 동계 정기 학술대회 초록집
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• pp.276-276
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• 2012

The interface morphology of organic active layers is known to play a crucial role in the performance of organic photovoltaic (OPV) cells. Especially, a controlled nanostructure with a large contact area between electron donor (D) and acceptor (A) layers is necessary to improve the power conversion efficiency (PCE) of the cells since the short exciton diffusion lengths in organic semiconductors limit the charge (hole and electron) separation before excitons recombination. In this work, we developed simple solvent treating methods to fabricate a nanostructured DA interface and applied them to enhance the PCE of ZnPc/C60 based small molecule OPV cells. Interestingly, it was observed that the solvent treatment on the donor layer prior to the deposition of the acceptor layer resulted in a significant decrease in PCE, which was due to an existence of undesirable voids at the DA interface. Instead, the solvent vapor treatment after the DA bilayer formation led to densely packed and well dispersed DA contacts. Consequently, 3-fold enhancement of PCE as compared to the untreated bilayer cell was accomplished.

• Biotechnology and Bioprocess Engineering:BBE
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• 제6권6호
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• pp.426-432
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• 2001

Perstractive fermentation is a good way to increase the productivity of bioreactors. Us-ing Propionibacteria as the model system, the feasibility of using supported emulsion liquid mem-brane(SELM) fro perstractive fermentation is assessed in this study. Five industrial solvents were considered as the solvent for perparing the SELM. The more polar a solvent, is the higher the par-tition coefficeint However, toxicity of a solvent also increases with its polarity. CO-1055(indus-trial decanol/octanol blend)has the highest partition coefficient toward propionic acid among the solvents that has no molecular toxicity toward Propionibacteria, A preliminary extraction study was conducted using tetradecane as solvent in a hydrophobic hollow fiber contactor. The results confirmed that SELM eliminates the equilibrium limitation of conventional liquid-liquid extrac-tion and allows the use of a non-toxic solvent with low partition coefficient.