• Applied Chemistry for Engineering
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• v.5 no.4
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• pp.573-579
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• 1994

1-O-oleoyl glycerol, 2-O-oleoyl myo-inositol and methyl 2-O-oleoyl-${\alpha}$-D-glucopyranoside were used as surfactants in this study. The solution properties and solubilization process of those nonionic surfactants were examined by the phase equilibria. As a result of this study, we have found that phase behavior of two component systems of surfactants/$H_2O$/cyclohexane depends on temperature respectively. The three phase regions of three component systems appeared in the temperature range of $27^{\circ}C{\sim}32^{\circ}C$, $36^{\circ}C{\sim}45^{\circ}C$ and $38^{\circ}C{\sim}52^{\circ}C$ and solubilization of water and oil was high in those three phase ranged As the temperature was varied in the two component systems, liquid crystals of hexagonal were observed to in the case of 1-O-oleoyl glycerol, and liquid crystal of lamella types were observed in the case of 2-O-oleoyl myo-inositol and methyl 2-O-oleoyl-${\alpha}$-D-glucopyranoside.

• Economic and Environmental Geology
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• v.36 no.5
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• pp.375-380
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• 2003

This study was carried out 1) to investigate the pH effect on solubilization of phenanthrene by biosurfactant in aqueous system and 2) to evaluate the pH effect on the biodegradation rate of phenanthrene in the presence and the absence of the biosurfactant by phenanthrene degraders. Tween 80, which is a chemically synthesized surfactant, showed greater solubilizing capacity than rhamnolipid. The solubilization capacity can be expressed as a MSR(molar solubilization ratio=moles of organic compounds solubilized per mole of surfactant). The calculated MSR of Tween 80 and rhamnolipid were 0.1449 and 0.0425 respectively. The kinetic study of phenanthrene solubilization by rhamnolipid showed that solubilization mechanism could reach equilibrium within 24 hours. Addition of 240 ppm rhamnolipid solution, which concentration is 4.3 times of Critical Micelle Concentration(CMC), caused 9 times solubility enhancement compared to water solubility. The highest solubilities were detected around a pH range of 4.5-5.5. Changes in apparent solubility with the changes in pH are possibly related to the fact that the rhamnolipid, an anionic surfactant, can form different structures depending on the pH. Two biodegradation experiments were performed in the absence and the presence of rhamnolipid, with the cell growth investigated using a spread plate method. The specific growth rates at pH 6 and 7 were higher than at the other pH, and the HPLC analysis data, for the total phenanthrene loss, confirmed the trends in the $\mu$(specific growth rate) values. In presence of rhamnolipid, maximum $\mu$ values shifted from around pH 5 which showed maximum enhancement of solubility in the abiotic experiment, compared to the $\mu$ values obtained without the biosurfactant. In this study, the increase in the observed specific grow rate(1.44 times) was not as high as the increase in solubilization(5 times). This was supported by the fact all the solubilized phenanthrene is not bioavailable to microorganisms.

• Applied Chemistry for Engineering
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• v.8 no.6
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• pp.881-885
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• 1997

The solubilizing capacity of GL-12, LAS, SLES aqueous solutions and that of mixed surfactant systems were studied using sudan III, which is oil-siluble dye. The solubilizing capacity of mixed surfactant systems was greatly influenced by the mixing ratios. Generally, the solubilizing capacity increased as the composition of GL-12 in the mixed systems increased. From the effect of NaCl on the solubilizing capacity, it was found that the solubilizate is located near the palisade layer in the GL-12/LAS system, and the solubilizate is located inside the micellar core in the GL-12/SLES mixed system. These differences in the location of slubilizate inside micelles result from the difference of molecular structure between LAS and SLES.

• Clean Technology
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• v.11 no.1
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• pp.1-12
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• 2005

In these studies, semibatch emulsion copolymerization of n-butyl acrylate (n-BA) as adhesive component and methyl metacrylate (MMA) as coagulant component was carried out in order to investigate the role of surfactant in aqueous phase for polymer cement. It was found that the particle size and concentration of final polymer are affected by surfactant type used. The effect of nonionic surfactants was shown in the decrease of polymer emulsion concentration and small emulsion particle in order of LE-50, NP-50 > CE-50, Tween 20 > TX-405 > Brij 35. In LE and NP (n=7-50) as nonionic surfactant, it could be obtained the stable polymer emulsion of 40% in aqueous phase with average particle size of 250-320 nm using over n=30. On the other hand, the effect of surfactant type in initial reactor charge was shown that when SDS as ionic surfactant was used, the polymer emulsion concentration was constant irrespective of the amount used, whereas CTAB as cationic surfactant and HN-100 as reactive surfactant were shown a tendency to the decrease of that. The effect surfactant type on final polymer particle size was shown in decrease by the order of SDS > CTAB > HN-100.

• Applied Chemistry for Engineering
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• v.10 no.4
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• pp.537-542
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• 1999

Removal of sulfur compounds in the petroleum products is essential for the prevention of sulfur oxides. However, conventional methods involving catalytic reactions are found to have some limitations in complete removal of harmful sulfur compounds and to require relatively high cost. Recently, desulfurization process using microorganisms is known to be promising in terms of excellent sulfur removal efficiency and reasonably low treatment cost. For the biodesulfurization process to be effective, the solubilization of sulfur compounds into aqueous solution is a prerequisite. In this study, polyoxyethylene nonionic surfactants were used in order to enhance the solubilization of sulfur spectrophotometer. The solubilization of sulfur compounds was found to increase with temperature and to bo abruptly increased at above 1 wt % surfactant solutions. It was also observed that the longer the hydrophobic chain of the surfactant molecule, the higher solubilizing power of a nonionic surfactant. It was found that the Tergitol series surfactants showed higher solubilizing capacity than Neodol series presumably due to the disruption of the regular packing in the hydrocarbon region of the surfactant aggregates.

• Journal of the Korean Applied Science and Technology
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• v.33 no.1
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• pp.51-57
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• 2016

In this study, we synthesized reactive surfactant which have functional radical group for effective chemical reaction. Reactive surfactant have been synthesized using synthesis of polyoxyethylene lauryl ether(POE 23) which is nonionic surfactant and methacrylic acid, acrylic acid. benzene was used as the solvent, p-TsOH was used as the catalyst. synthesized surfactant was confirmed by FT-IR, $^1H$-NMR spectra, and elemental analysis. Evaluation of physical properties was measured HLB, cloud point, surface tension, the critical micelle concentration, emulsifying power. HLB number was evaluated 11.62 to 12.09 range. The Critical Micelle Concentration(cmc) values evaluated was $1{\times}10^{-4}{\sim}5{\times}10^{-4}mol/L$ by surface tension method. The cloud point was $35^{\circ}C$, $39^{\circ}C$ each. The emulsifymvcqa ing properties of the synthesized surfactants was lower than polyoxyethylene lauryl ether. In addition, soybean oil was better than benzene. The experimental results confirmed the ester bond, the yield of 93.27%, 94.49% was found.

• Journal of Conservation Science
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• v.28 no.1
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• pp.21-27
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• 2012

In the Chosun period, the noble class usually buried the dead bodies in the lime-covered tomb. Recently their costumes are excavated while maintaining the shape. However, the textiles discovered from the inside have been degradated by a body and moisture. To conserve these textiles one of the most important thing is how to clean these textiles right after the excavation. The purpose of this study is to examine the effects of wet cleaning to minimize the color change of textile remains. For this purpose, silk and cotton were dyed with natural dyes (7 red, 1 blue, 6 yellow, 4 green and 4 purple colors), then they were kept for 6 months with pork meat at $10^{\circ}C$, and were washed by four cleaning solutions (water, anionic surfactant (SDS), non-ionic surfactant (Triton X-100) and natural surfactant (saponin)) at $20^{\circ}C$ and $40^{\circ}C$. The color change was evaluated by color difference (${\Delta}E$) between non-treated and after washed samples. From the results, it was found that the color changes are significantly different depending on the washing temperature, textile material, the cleaning agents and the type of dyes.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 1996.11a
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• pp.54-57
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• 1996

• Applied Chemistry for Engineering
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• v.8 no.3
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• pp.473-481
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• 1997

Enhanced videomicroscopy was used to observe the dynamic behavior which occurred when water containing pure nonionic surfactant was carefully contacted with equal volumes of polar oils such as oleyl alcohol and oleic acid at various temperatures. A key component of the system is a vertical-stage microscope which provides for stable interfaces by locating the oil above the denser aqueous phase. This arrangement allowed intermediate phases formed at the surface of contact to be clearly observed, as well as any spontaneous emulsification which developed. Contacting experiments with $C_{12}E_5$ as the surfactant and with pure oleyl alcohol and oleic acid soils showed little activity below the cloud point but vigorous activity at higher temperatures including formation of an intermediate lamellar liquid crystalline phase. Diffusion path theory, which allows prediction of spontaneous emulsification resulting from diffusion and of intermediate phase formation during contacting processes, was used to understand the dynamic behavior seen during contacting experiments. Tentative diffusion paths for the contacting experiments with pure oleyl alcohol were presented with the aid of a partial phase diagram of the oleyl alcohol-water-$C_{12}E_5$ system.

• Applied Chemistry for Engineering
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• v.5 no.2
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• pp.274-284
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• 1994

Phase Inversion Temperature (PIT) measurements showed that the addition of polar components such as oleyl alcohol and oleic acid to the system comprising n-dodecylpentaoxyethylene monoether ($C_{12}E_5$), nonpolar oil (n-hexadecane) and water produced large reductions in the PIT. The PIT was lowered as the additive-to-surfactant ratio in the surfactant films in the microemulsion phase was increased. Another dramatic effect of additive was the manner in which it affects the volume of the microemulsion phase at the PIT of the oil and water solubilization characteristics. Microemulsion phase volume was increased rapidly with decreasing PIT, i.e., with increasing amounts of additive in the system. Also with a decrease in PIT, the solubilization parameters of both oil and water in the microemulsion phase were strikingly increased. Even though soil removal data were not available for the conditions where our results obtained, PIT measurement seems a useful starting point for estimating conditions when middle-phase microemulsion formation and its associated high solubilization of oil can be expected.