계면활성제용액-경유 간 계면장력과 용해도 상관관계 연구

정승우(Seung Woo Jeong),허정현(Jeong Hyun Hur) 大韓環境工學會 2013 대한환경공학회지 Vol.35 No.1

토양정화를 위한 토양 세정 및 세척 공정에서 계면활성제 선택 기준과 가장 중요한 설계인자는 오염물질의 용해도이다. 계면활성제의 오염물질 용해도는 오염물질과 평형상태를 만든 후 Dichrolomethane을 이용한 추출, 증발, 농축 등의 전처리과정을 거쳐야 한다. 따라서 계면활성제 용액 내 유류 오염 물질의 용해도 분석은 많은 시간과 재료를 필요로 한다. 계면장력은 계면활성제용액과 유류오염물질 사이에 유지되는 힘을 지칭하는 것으로 용해도와 밀접한 관계를 가진다. 본 연구는 계면활성제용액과 경유 간 계면장력과 용해도를 측정하여 계면장력과 용해도간 상관관계를 정립하므로 신속한 계면 장력 측정을 통한 용해도를 가늠할 수 있는 방안을 제시하였다. 계면장력과 유류용해도간 상관관계를 평가한 결과 두 특성은 기하급수적인 반비례관계를 보였다. 즉, 계면장력이 5 dyne/cm 이상조건에서 경유의 용해도는 크게 차이를 보이지 않다가 1 dyne/cm 이하에서 경유의 용해도는 급격하게 증가하였다. 앞으로 계면활성제용액 간 계면장력을 우선적으로 측정해 본다면 토양정화에 적합한 계면활성제 종류 및 농도를 매우 신속하고 효율적으로 선택할 수 있을 것으로 판단된다. Solubility of oil contaminants in surfactant solutions plays an important role in selecting a suitable surfactant type for soil remediation. Solubility measurement procedures consist of making an equilibrium between surfactant solution and oil, solvent extraction using dichloromethane, and condensation for gas chromatography analysis. Solubility measurement requires time consumption and lots of materials. Interfacial tension is the contracting force between two immiscible liquids, surfactant solution and oil, and also closely related to solubility of oil. This study established a relationship between the interfacial tension and solubility of diesel fuel in surfactant solution and suggested a quick method to estimate solubility of oil in a surfactant solution by measuring its interfacial tension. The results of this study showed that the solubility of diesel fuel in surfactant solution was exponentially increased by decreasing the interfacial tension between two immiscible liquids. The solubility of diesel fuel was significantly increased under the interfacial tension conditions below 1 dyne/cm, while the solubility change was not apparent under the interfacial tension conditions beyond 5 dyne/cm. Interfacial tension measurements may allow us to quickly select an efficient surfactant and its concentration for soil remediation.

Renormalization group corrections to the modified perturbed hard sphere chain equation of state for vapor liquid equilibria and interfacial tension of pure and binary mixtures

Choi, J.S.,Bae, Y.C. Elsevier Scientific Pub. Co 2016 Fluid phase equilibria Vol.430 No.-

The interfacial tensions of pure fluids and binary fluid mixtures are described following an investigation of phase behavior. A modified version of the perturbed hard sphere chain (PHSC) equation of state (PHSC-CL EOS) is developed by applying the chain length dependence contribution to the PHSC EOS. The density gradient theory (DGT) is combined with the proposed model to account for both the phase equilibria and the interfacial tension. The influence parameter, the only input of the DGT with EOS to calculate the interfacial tension of the fluid, is considered an adjustable parameter for each fluid. The PHSC-CL EOS accurately describes the vapor liquid equilibria (VLE) and interfacial tensions of fluids away from the critical region. It is combined with a renormalization group theory to consider the contribution of long range fluctuations in the near critical region. The calculation procedure is based on White's work and the phase space cell approximation is adopted for mixtures. The VLE and interfacial tensions are obtained with good agreement to experimental data for linear alkanes, cyclo hexane, benzene, toluene, carbon dioxide, and their binary mixtures.

The effect of SEBS on interfacial tension and rheological properties of LDPE/PS blend

Nam, G. J.,Kim, K. Y.,Lee, J. W. Wiley Subscription Services, Inc., A Wiley Company 2005 Journal of applied polymer science Vol.96 No.3

<P>The effects of SEBS as a compatibilizer on the interfacial tension and rheological properties of LDPE/PS blend have been studied. Interfacial tension was measured by the breaking thread method. The measured interfacial tension of the LDPE/PS blend was 8.26 dyn/cm. It decreased rapidly with SEBS contents to 1 wt % and then leveled off to a saturation value, 3.6 dyn/cm. Dynamic oscillatory shear, elongational viscosity, and recovery after elongation were measured as the rheological properties. Storage modulus at low frequencies decreased with SEBS contents to 1 wt %. More addition of SEBS, however, increased the storage modulus at low frequencies. Similar behaviors could be observed in elongation viscosity and recovery after elongation. Hardening of elongational viscosity and recovery after elongation were reduced with 1 wt % SEBS, and they enhanced again with more SEBS contents. This means that there is a critical concentration of SEBS that acts as a compatibilizer and reduces the interfacial tension. More SEBS than the critical concentration saturates the interface and increases the elasticity of the LDPE/PS blend, while maintaining the interfacial tension between LDPE and PS constant. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 96: 905–911, 2005</P>

Interfacial Tension-Mediated Droplet Fusion in Rectangular Microchannels

홍종인,최민석,Joshua B. Edel,Andrew J. deMello 한국바이오칩학회 2009 BioChip Journal Vol.3 No.3

We successfully demonstrate the merging of aqueous droplets within a microfluidic channel mediated by a difference in interfacial tension. Interfacial tension is shown to have a significant influence on the hydrodynamic forces associated with a segmented flow in a rectangular microchannel and results in the possibility of merging multiple droplets in a simple fashion. This facility is important in allowing droplet-based microfluidic systems to be used as synthetic tools in complex reaction processing.

A simple approach to determine the equilibrium shape and position of sandwiched polymer droplets

Hyun, Dong Choon,Jeong, Unyong,Ryu, Du Yeol Wiley Subscription Services, Inc., A Wiley Company 2007 Journal of polymer science. Part B, Polymer physic Vol.45 No.19

<P>The thermodynamic shape and position of a polymer drop sandwiched between two polymer melt plates were predicted by simulating the change of the interfacial energy according to various shapes and position of the drop. The calculation results were in a precise coincidence with the experimental results exhibiting lens, spreading, and encapsulation. The simple formula and easy concept of the calculation can be useful to predict the morphology of immiscible ternary blends with the information of the interfacial tensions. © 2007 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 45: 2729–2738, 2007</P>

Experimental and theoretical investigations on the carbon dioxide gas hydrate formation kinetics at the onset of turbidity regarding CO2 capture and sequestration processes

Bahman ZareNezhad,Mona Mottahedin,Farshad Varaminian 한국화학공학회 2013 Korean Journal of Chemical Engineering Vol.30 No.12

The carbon dioxide gas hydrate formation kinetics at the onset of turbidity is experimentally and theoretically investigated. It is shown that the time-dependent heterogeneous nucleation and growth kinetics are simultaneously governing the hydrate formation process at the onset of turbidity. A new approach is also presented for determination of gas hydrate-liquid interfacial tension. The CO2 hydrate-liquid interfacial tension according to the suggested heterogeneous nucleation mechanism is found to be about 12.7 mJ/m2. The overall average absolute deviation between predicted and measured CO2 molar consumption is about 0.61%, indicating the excellent accuracy of the proposed model for studying the hydrate-based CO2 capture and sequestration processes over wide ranges of pressures and temperatures.

보조계면활성제가 노닐페놀 에톡실레이트 계면활성제, 탄화수소 오일, 물로 이루어진 삼성분계의 상평형 및 동적거동에 미치는 영향

임홍규 ( Heung Kyoon Lim ),이슬 ( Seul Lee ),모다희 ( Da Hee Mo ),임종주 ( Jong Choo Lim ) 한국화학공학회 2012 Korean Chemical Engineering Research(HWAHAK KONGHA Vol.50 No.6

본 연구에서는 보조계면활성제 첨가가 nonylphenol ethoxylate (NP) 계면활성제, 물, 탄화수소 오일의 3성분으로 이 루어진 시스템의 평형 및 동적 거동에 미치는 영향을 살펴보았다. 실험에서 사용한 펜탄올, 옥탄올, 데칸올 등의 보조 계면활성제는 모두 소수성 첨가제로 작용하였으며, 소수성 증가 효과는 알코올의 사슬 길이 증가 및 첨가량 증가에 따 라 증가하였다. 계면활성제 시스템이 친수적인 조건에서는 비극성 오일의 종류에 상관없이 시간에 따라 오일의 크기 가 감소하였으며, 마이셀 용액에 의한 탄화수소 오일의 가용화는 diffusion-controlled 메커니즘이 아닌, interfacecontrolled 메커니즘을 따름을 확인할 수 있었다. 반면에 소수성 조건에서는 과포화로 인하여 일어나는 자발적 유화 현 상과 물과 계면활성제의 오일상으로의 확산으로 인한 오일의 크기 증가가 관찰되었다. 비극성 탄화수소 오일과 계면 활성제 수용액 사이의 시간에 따른 계면장력 측정 결과는 동적 거동 실험결과와 일치하는 경향을 나타내었다. 한편 middle-phase 마이크로에멀젼을 포함한 3상이 형성되는 조건에서는 매우 낮은 계면장력으로 인하여 오일이 수용액 상 에 빠른 속도로 가용화되었고 작은 방울 형태로 유화되었다. In this study, the effects of cosurfactant on phase equilibrium and dynamic behavior were studied in systems containing nonylphenol ethoxylate (NP) surfactant solutions and nonpolar hydrocarbon oils. All the cosurfactants used during this study such as n-pentanol, n-octanol and n-decanol acted as a hydrophobic additive and the hydrophobic effect was found to increase with both increases in chain length and amount of addition of a cosurfactant. Dynamic behavior studies under hydrophilic conditions showed that the solubilization of hydrocarbon oil by NP micellar solution is controlled by an interface-controlled mechanism rather than a diffusion-controlled mechanism. Both spontaneous emulsification of water into oil phase and expansion of oil drop were observed under lipophilic conditions because of diffusion of surfactant and water into oil phase. Under conditions of a three phase region including a middle-phase microemulsion, both rapid solubilization and emulsification of oil into aqueous solutions were found mainly due to the existence of ultralow interfacial tension.

AEO 비이온 계면활성제/Cosurfactant/물/오일 시스템의 상거동에 관한 연구

고현길,이종기,박소진,박병덕,홍종규,박상권,임종주 한국화학공학회 2002 Korean Chemical Engineering Research(HWAHAK KONGHA Vol.40 No.3

본 연구에서는 AEO계 비이온 계면활성제, 물, D-리모넨의 3성분으로 이루어진 시스템 및 cosurfactant를 첨가할 경우에 대한 상평형 실험을 수행하였다. 비이온 계면활성제, D-리모넨, 물로 이루어진 3성분 시스템에 대한 상평형 실험 결과에 의하면 middle-phase 마이크로에멀젼(microemulsion, μE)이 excess water와 excess oil 상들과 평형을 이루는 3상은 형성되지 않거나 매우 적은 영역에서 형성되었으며, 생성된 단일상의 μE 구조는 전기전도도 측정으로부터 W/O μE으로 판명되었다. 또한 cosurfactant로서 butyl diglycol(BDG), butyl triglycol(BTG)을 첨가한 결과, cosurfactant 첨가량을 증가시킴에 따라 middle-phase μE을 포함한 3상이 생성되는 온도는 감소하였고 3상이 존재하는 온도 범위는 증가하였다. Microemulsion을 사용하여 비극성 오일인 abietic acid, triolein과 윤활유에 대한 가용화 실험을 수행한 결과, W/O μE의 가용화력이 가장 크게 나타났으며, cosurfactant를 첨가할 경우 계면장력이 낮아짐에 따라 가용화도는 증가하였다. In this study, phase behavior study was performed for ternary systems containing AEO nonionic surfactant, water and D-limonene as a function of surfactant concentration and temperature. The results in the ternary systems showed that a three phase region containing a middle-phase microemulsion(μE) in equilibrium with excess water and excess oil phase was not found or formed over a very limited small region. On the other hand, addition of butyl diglycol(BDG) and butyl triglycol(BTG) as cosurfactants lowered the temperature for the formation of a three phase region including a middle-phaseμE and produced a three phase region over a wide range of temperatures. The solubilization experiments for abietic acid, triolein, and lubricant using three different types of μEs showed that the maximum oil removal was achieved with a water-in-oil(W/O)μE in all cases. Addition of a cosurfactant promoted the solubilization mainly due to a decrease in interfacial tension.

Interfacial tension between decane saturated with methane and water from 283.2 K to 298.2 K under pressures upto 10 Mpa

Masamichi Kodera,Kosuke Watanabe,Maxence Lassiège,Saman Alavi,Ryo Ohmura 한국공업화학회 2020 Journal of Industrial and Engineering Chemistry Vol.81 No.-

Interfacial tension is one of the most important physical properties for high-precision simulations todevelop the methods of preventing plugging of pipelines in the oil and natural gas industry. This paperreports experimental data with the pendant drop method for the interfacial tension of adecane + methane + water system at temperatures between 278.2 K to 298.2 K and pressures up to10 MPa. The data show that in this temperature range the interfacial tension in the decane + methane+ water system decreases almost linearly with increasing temperature. The results also show that byincreasing the pressure of methane, the interfacial tension decreases from 53.98 mN m 1 to50.23 mN m 1 at 283.2 K and 52.23 mN m 1 to 49.74 mN m 1 at 288.2 K. The nature of the methanepressure dependence of the interfacial tension changes for pressures above around 2.00 MPa. Theinterfacial tension decreases with the pressure up to 2.00 MPa, but has no pressure dependence above2.00 MPa. It may be inferred that the decane/water interface is saturated with methane at pressuresaround 2.00 MPa and at higher pressure the interfacial tension is no longer affected by the presence ofmethane.

수적(垂滴)법을 이용한 이산화탄소 지중저장 조건에서의 염수-이산화탄소 간 계면장력 측정

박규령,안혜진,김선옥,왕수균,Park, Gyuryeong,An, Hyejin,Kim, Seon-ok,Wang, Sookyun 한국지하수토양환경학회 2016 지하수토양환경 Vol.21 No.6

This experimental study was aimed to estimate interfacial tension of brine-$CO_2$ by using a pendant bubble method and image analysis. Measurements were performed for wide ranges of temperatures, pressures, and salinities covering reservoir conditions in Pohang basin, a possible candidate for $CO_2$ storage operation in Korea. The profiles of $CO_2$ bubbles in brine obtained from image analysis with the densities of brine and $CO_2$ from previous studies were applied to Laplace-Young equation for calculating interfacial twnsion in brine-$CO_2$ system. The experimental results reveals that the interfacial tension is significantly affected by reservoir conditions such as pressure, temperature and water salinity. For conditions of constant temperature and water salinity, the interfacial tension decreases as pressure increases for low pressures (P < $P_c$), and approaches to a constant value for high pressures. For conditions of constant pressure and water salinity, the interfacial tension increases as temperature increases for T < $T_c$, with an asymptotic trend towards a constant value for high temperatures. For conditions of constant pressure and temperature, the interfacial tension increases with increasing water salinity. The trends in changes of interfacial tension can be explained by the effects of the reservoir conditions on the density difference of brine and $CO_2$, and the solubility of $CO_2$ in brine. The information on interfacial tensions obtained from this research can be applied in predicting the migration and distribution of injecting and residual fluids in brine-$CO_2$-rock systems in deep geological environments during geological $CO_2$ sequestrations.