• 자원리싸이클링
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• 제8권3호
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• pp.31-36
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• 1999

아크릴로니트릴 제조공정 중 부산물로 생성되는 물과 아세토니트릴 공비혼합물을 분비, 회수하기 위하여 혼합용매로서 toluene-ethylacetate를 선택하여 $25^{\circ}C$에서 4성분계 toluene(1)-water(2)-acetonitrile(3)-ethylacetate(4)에 대한 액-액평형 데이터를 구하였다. Tie-line 계산치를 예측하기 위하여 실험치를 UNIFA 모델식의 파라미터와 상호연관시켜 비교하였다. 또한 용매의 성능을 비교하기 위하여 분배계수 및 선택도를 고찰하였다.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2009년도 추계학술대회 논문집
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• pp.518-519
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• 2009

투과증발은 저 에너지 분리기술로서 공비혼합물의 분리 및 유기화화물을 선택적으로 분리하는 공정에 활용되고 있다. 투과증발공정을 위한 막으로 쓰이는 대표적인 고분자 재료인 친수성 고분자 PVA(Poly(vinyl alcohol)는 하이드로실 그룹을 포함하고 있어 물에 대한 선택도가 뛰어난 장점을 가지고 있다. 그러나 PVA는 물에 대한 친화력이 높아 투과증발막으로 적용하기 위해서는 내수성을 향상시키기 위하여 가교시킨후 투과증발막으로 사용가능하다. 본 연구에서는 PVA 분리막을 투과증발막으로 적용하기 위하여 PVA를 전기방사에 의해 나노섬유로 제조하고 제조된 나노섬유가 수용액에서 내수성을 갖게 하기 위해 10-70%의 KOH수용액에 가교화 하여 특성을 알아보았다.

• 한국산업융합학회 논문집
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• 제8권1호
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• pp.37-45
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• 2005

Adsorption equilibrium data of pure solvent vapors (n-Hexane, Toluene, MEK) as well as their binary mixtures on activated carbon (sorbonorit $B_4$) were experimentally determined in the range of 293.2~323.2 K and beyond saturated vapor pressure corresponding to experimental temperature. Langmuir, Freundlich, LRC, W-VSM, FH-VSM were estimated for the predication of single component as well as binary mixtuer systems. The isosteric heat of adsorption at infinite dilution of pure n-hexane, toluene, MEK on activated carbon were 45.18, 25.85, 34.62 Kcal/mol, respectively, also, n-hexane-toluene binary adsorption of activated carbon formed an azeotrope at 293.2 K and total pressure 5.1~10.3 mmHg.

• 한국막학회:학술대회논문집
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• 한국막학회 2003년도 The 4th Korea-Italy Workshop
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• pp.77-80
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• 2003

Hydrocarbon-hydrocarbon separations are one of the most important processes in petroleum refining. Distillation process has been used for separating hydrocarbons, but this conventional process is very energy consuming. Pervaporation separation through polymeric membranes is an emerging process alternative to distillation because of energy savings, compact system installation, reduced capital investment, and other performance attributes. In hydrocarbon separations, polymeric membranes are easily swollen by hydrocarbons and can lose mechanical strength. Chemically robust membranes are needed for the separation of hydrocarbons. In this study, the blend membrane was applied to separate benzene and cyclohexane. This is a model system for aliphatic and aromatic separation. Cyclohexane is also physically very similar to benzene and as a result of the very closing boiling points (0.6$^{\circ}C$), benzene and cyclohexane form an azetrope. Thus the system provides a good model for azeotrope breaking by pervaporation. The semi-quantitative thermodynamic model predicts that the calculated selectivity increases with increasing Hydrin contents in the blend membranes. Pervaporation experiments utilizing various operating temperatures and feed concentrations with different blend membranes are compared with the result from semi-quantitative thermodynamic calculations.

• 멤브레인
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• 제17권1호
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• pp.1-13
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• 2007

분리막을 이용한 투과증발공정은 에너지 소모가 적고 설치비와 운영비면에서 우수한 효과를 볼 수 있기 때문에 증류공정을 대신할 수 있는 공정으로 주목받고 있다. 특히 석유화학공정은 공정 중에 에너지 소모가 크고, 많은 화합물들이 공비혼합물을 이루고, 새로운 공정을 설치하기 위해서는 작은 공간을 필요로 하기 때문에 투과증발공정은 증류공정을 대체할 수 있는 매우 유력한 후보이다. 벤젠/시클로헥산을 포함하는 방향족 화합물의 분리, 올레핀/파라핀 분리, 자일렌 이성질체의 분리, 반응성 단량체의 회수, 가솔린으로부터 황 화합물의 제거 등에 투과증발공정을 응용하는 많은 연구가 이루어졌으며, 상용화가 되고 있다.

• 에너지공학
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• 제2권3호
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• pp.308-314
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• 1993

15mbar 정합하에서 n.dodecane-1.decanol-1.dodecanol 혼합물의 삼성분계 및 각 이성분계의 기액평형 데이타와 비점을 측정하였다. 측정된 기액평형 데이타는 g$^{E}$ 모델식 인 Margules, van Laar, Wilson, NRTL, UNIQA 식에 의해 상관관계를 알아보았다. 이성분계 데이타는 Redlich-Kister의 적분법에 의해 열역학적으로 검토하였으며, 삼성분계 데이터 역시 McDermott-Ellis에 의한 two-point consistency test에 의해 질적으로 검토되었다. 이성분계의 기액평형 데이타 중에 n.dodecane-1.decanol계 만이 공비점을 보였다.

• 설비공학논문집
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• 제14권4호
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• pp.332-340
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• 2002

In these days, environmental concerns have been increased throughout the industry and community worldwide. To prevent the ozone depletion, ozone depletion potential of a refrigerant must be zero. Simultaneously, a refrigerant with low GWP (global warming potential) is very demanding to induce green house effect. Chlorine-free HFC-l34a is a refrigerant widely used for automotive air-conditioning system because its destruction potential is ecologically zero. Although HFC-l34a has no ozone depletion potential, its global warming potential is so high that it is not considered as a perfect alternative refrigerant that is acceptable for long-term use. In this paper, experimental measurement has been carried out to analyze the performance characteristics of automotive air-conditioning system using HFC-152a, which has low GWP and zero ODP. Also mixed refrigerant that is composed of HFC-152a and $CF_3$ was applied to investigate an alternative possibility for the automotive airconditioning system. As a result of this study, we could draw following conclusions; With respect to the variation of the rotational speed of compressor, outside air temperature and flow rate, the heat amount of evaporator and compressor and performance coefficient was varied.

• 태양에너지
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• 제18권1호
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• pp.69-79
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• 1998

This paper is concerned about the performance of HCFC22 alternative refrigerants used in heat pumps and industrial chillers. A water-to-water breadboard heat pump with counter-current heat exchangers and a hermetic compressor was built to carry out the experiments with various refrigerants. For each test, more than 40 temperatures, 4 pressures, power input, mass flow rates of the heat transfer fluids were measured. Refrigerants tested were HCFC22, R290(Propane), an azeotrope of 45%Propane/55%R134a mixture, and a nonazeotropic mixture of Calor 50. All tests were conducted under ARI test A condition. It is found that the COP and capacity of propane were 18% and 2.5% higher than those of HCFC22 while the COP and capacity of 45%Propane/55%R134a mixture were 3.5% and 5.3% higher than those of HCFC22 respectively. Also the COP and capacity of Calor 50 were 17% and 7.8% higher than those of HCFC22. Compressor discharge temperatures of alternative refrigerants were roughly $35^{\circ}C$ lower than that of HCFC22 indicating that these refrigerants are good from the view point of compressor reliability. The charging amounts for the alternative refrigerants were reduced by 40-60% as compared to that of HCFC22. Overall, it can be said that hydrocarbon containing alternative refrigerants are excellent in thermodynamic performance but should be used with considerable care due to their flammability.

• 에너지공학
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• 제2권2호
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• pp.225-230
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• 1993

n-dodecane-1-decanol, n-dodecane-1-dodecanol 및 1-decanol-1-dodecanol계 의 14$0^{\circ}C$ 등온 기액평형 데이타를 static method로써 Head Space Gas Chromatography (H.S.G.C)를 이용하여 측정하였다. 액상의 비이상성을 고려하여 계산된 활동도계수는 Margules, Van Laar, Wilson, NRTL g$^{E}$ 모델을 이용하여 상관관계를 구하였으며, Redlich-Kister의 열역학적 일치성 시험을 통해 데이타의 신빙성을 확인하였다. 측정한 이성분계중 n-dodecane-1-decanol계는 최소 공비점을 가짐을 알 수 있었다.

• Membrane and Water Treatment
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• 제8권5호
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• pp.483-498
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• 2017

Novel mixed matrix membranes of Sodium Alginate (NaAlg) were developed by the incorporation ofunmodified, modified Phosphomolybdic acid (PMA) then cross-linked with glutaraldehyde externally. These membranes were prepared by the solution casting technique. Pervaporation (PV) experiments have been performed with pure NaAlg, unmodified NaAlg-PMA5, NaAlg-PMA10, modified NaAlg-mPMA5, and NaAlg-mPMA10 (wt. % of PMA 5 and 10) at 30, 40 and $50^{\circ}C$, to separate water-isopropanol feed mixtures containing 10-30 wt. % of water. Pervaporation results of NaAlg-mPMA10 produced a highest separation factor of 9028 with a flux of $0.269kg/m^2.h$ for 10 wt. % of water containing feed mixture. Both separation factor and flux for water increased significantly with increasing content of mPMA into NaAlg; a significant improvement in PV performance was observed for NaAlg-mPMA5 and NaAlg-mPMA10 membranes when compared to pure NaAlg& PMA-5, PMA-10 membrane.