• International Journal of Fluid Machinery and Systems
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• v.4 no.2
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• pp.223-228
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• 2011

The performance characteristics of centrifugal pump were measured experimentally when running with tap water and drag-reducing surfactant (Octadecyl dimethyl amine oxide (OB-8)) solutions. Tests have been performed on five cases of surfactant solutions with different concentrations (0ppm (tap water), 200ppm, 500ppm, 900ppm and 1500ppm) and four different rotating speeds of pump (1500rpm, 2000rpm, 2500rpm and 2900rpm). Compared with tap water case, the experimental results show that the total pump heads for surfactant solution cases are higher. And the pump efficiency with surfactant solutions also increases, but the shaft power for surfactant solutions cases decreases compared to t hat for tap water. There exists an optimal temperature for surfactant solutions, which maximizes the pump efficiency.

• Proceedings of the SCSK Conference
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• 2003.09b
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• pp.369-369
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• 2003

Viscarin is a tradename given to viscosifying carrageenans manufactured by FMC BioPolymer. The suitability of Vis car ins as rheology agents in mild cleansing applications has been investigated. Rheological properties, foam volume and clarity were measured to determine the impact of including 1 % Viscarin on 10% solutions of the following surfactants: acylglutamate, cocoamidopropyl betaine, PEG-80 laurate, sodium lauryl sulphate and sodium lauryol sarcosinate. Viscosity, pseudoplasticity and thixotropy of Viscarin/surfactant solutions varied with surfactant type. In all cases, the addition of Viscarin substantially increased viscosity. For example, at a shear rate of 1 sol, all surfactant solutions had viscosities <0.1 Pa s while viscosities of Viscarin/surfactant solutions ranged from 10 to 60 Pa s. By comparison, a solution of 1 % Viscarin had a viscosity of 0.3 Pa s. Clarity of surfactant solutions decreased in all cases on the addition of Viscarin. However, it was found that by including a mild solubilizing surfactant, such as PEG 40 hydrogenated castor oil, crystal clarity could be maintained in Viscarin/surfactant solutions. Viscarin increased the foam volume of sodium lauryolsarcosinate solutions from 10 ml to 220 ml and had no impact on the foam volume of the other surfactants tested. These results were used to formulate a clear, ultra-mild foaming cleansing gel based on sodium lauryol sarcosinate and Viscarin without the need for a secondary, foam-boasting surfactant. A mild shampoo was also formulated. Both products have excellent skin-feel and are capable of suspending bubbles and solid inclusions.

• Korea-Australia Rheology Journal
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• v.17 no.4
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• pp.157-164
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• 2005

Hydrodynamic characteristic of surfactant drag-reducing flows is still not fully understood. This work investigated the temperature and diameter effect on hydrodynamic characteristic of cationic surfactant drag reducing flows in pipes. Solution of oleyl bishydroxyethyl methyl ammonium chloride (Ethoquad O/12), 900 ppm, as a cationic surfactant and sodium salicylate (NaSal), 540 ppm, as a counter-ion was tested at 12, 25, 40, and $50^{\circ}C$ in pipes with diameter of 13, 25, and 40 mm. Drag reduction effectiveness of this surfactant solution was evaluated in 25 mm pipe from 6 to $75^{\circ}C$. Rheological characteristic of this solution was measured by stress control type rheometer with cone-and-plate geometry. Scale-up laws proposed by previous investigators were used to evaluate the flow characteristic of the solution. It was found that this surfactant solution has clear DR capability until $70^{\circ}C$. Result of this work suggested that temperature has a significant influence in changing the hydrodynamic entrance length of surfactant drag reducing flows. From rheological measurement, it was found that the solution exhibits Shear Induced Structure at all temperatures with different degree of peak viscosity and critical shear rate.

• Bulletin of the Korean Chemical Society
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• v.18 no.3
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• pp.300-305
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• 1997

Effect of a nonionic surfactant, Tween 20 on the adsorption and kinetic mechanism for the hydrolysis of a microcrystalline cellulose, Avicel PH 101, by endoglucanase Ⅰ (Endo Ⅰ) and exoglucanase Ⅱ (Exo Ⅱ) isolated from Trichoderma viride were studied. The Langmuir isotherm parameters, amount of maximum adsorption (Amax) and adsorption equilibrium constant (Kad) for the adsorption, were obtained in the presence and the absence of nonionic surfactant. On the addition of Tween 20, the Kad and Amax values of Exo Ⅱ were decreased, while those of Endo Ⅰ were not affected. These indicate that the adsorption affinity of Exo Ⅱ on the cellulose is weakened by nonionic surfactant, and the surfactant enhanced desorption of Exo Ⅱ from insoluble substrate. The enzymatic hydrolysis of the cellulose can be described by two parallel pseudo-first order reactions using the percentages of easily (Ca) and hardly (Cb) hydrolyzable cellulose in Avicel PH 101 and associated rate constants (ka and kb). The Ca value was increased by adding Tween 20 for all enzyme samples (Exo Ⅱ, Endo Ⅰ and their 1:1 mixture) implying that the low-ordered crystalline fraction in the cellulose may be partly dispersed by surfactant. The ka value was not affect by adding Tween 20 for all enzyme samples (Exo Ⅱ, Endo Ⅰ and their 1:1 mixture). The kb value of Exo Ⅱ was increased by adding Tween 20, while that of Endo Ⅰ was not affected. This suggests that the surfactant helps the Exo Ⅱ desorb from microcrystalline cellulose, and increase the hydrolysis rate. These results were show that the increase of hydrolysis of cellulose by the nonionic surfactant is due to both the activation of Exo Ⅱ and partial defibrillation of the cellulose.

• KSBB Journal
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• v.22 no.1
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• pp.43-47
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• 2007

The effect of surfactant on the hydrolysis of used newspaper was investigated. The most suitable surfactant for the pretreatment stage was found to be NP-series surfactants among 9 kinds of non ionic surfactants. Process parameters such as surfactant concentration, mixing speed, pretreatment temperature and time were tested to optimize for maximum digestibility and 0.5%, 100rpm, 30$^{\circ}C$, and 1 h were found to be optimum, respectively. In order to maximize digestibility, substrate was pretreated with NP-20 and then the pretreated substrate was hydrolyzed by adding TW-80. The effect of surfactant on the hydrolysis of previously surfactant-pretreated newspaper was marginal. Therefore, the digestibility with the addition order of enzyme and surfactant was investigated by using surfactant only in hydrolysis stage. The results show that digestibility was more lowered as the surfactant addition after adding enzyme to substrate was more delayed.

• Korean Chemical Engineering Research
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• v.45 no.3
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• pp.226-233
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• 2007

In this study, the effects of additives such as ionic surfactant and cosurfactant were studied on the solubilization of sulfur compounds contained in the crude oil by Tergitol series nonionic surfactants. It was found that the addition of an ionic surfactant such as sodium oleate, potassium oleate, CTAB and DTAB did not enhance solubilization capacity of Tergitol series nonionic surfactant. On the other hand, the addition of a long-chain alcohol as a cosurfactant increased the solubilization of sulfur compounds in the crude oil. The effect of alcohol was found to become reduced with an increase in the amount of crude oil used mainly due to partitioning phenomena of an nonionic surfactant. The enhancement of solubilizing capacity of Tergitol series nonionic surfactant with addition of a cosurfactant was associated with a decrease in interfacial tension between crude oil and surfactant solution. The pH of Tergitol nonionic surfactant solution did not affect the solubilization of sulfur compounds. Finally, it was found that the growth of sulfur reducing microoganisms was not greatly affected by both addition of nonionic surfactant and cosurfactant.

• Journal of Soil and Groundwater Environment
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• v.17 no.1
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• pp.13-21
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• 2012

This study reports a surfactant-enhanced in-situ remediation treatment at a test site which is located in a hilly terrain. The leakage oils from a storage tank situated on the top of the hill contaminated soils and groundwater in the lower elevation. Sixteen vertical injection wells (11 m deep) were installed at the top of the hill to introduce 0.1-0.5 vol.% of non-ionic Tween-80 surfactant. The contaminated area that required remediation treatment was about $1,650\;m^2$. Two cycles of injecting surfactant solution followed by water were repeated over approximately 7.5 months: first cycle with 0.5 month of surfactant injection followed by 3 months of water injection, and second cycle with 1 month of surfactant followed by 3 months of water injection. The seasonal fluctuation in groundwater table was also considered in the selection of periods for surfactant and water injection. The results showed that the initial Total Petroleum Hydrocarbon (TPH) concentration of 1,041 mg/kg (maximum 3,605 mg/kg) was reduced significantly down to 76.6 mg/kg in average. After 2nd surfactant injection process finished, average TPH concentration of soils was reduced to 7.5% compared to initial concentration. Also, average BTEX concentration of soils was reduced to 10.8%. This resultes show that the surfactant enhanced in-situ remediation processes can be applicable to LNAPL contaminated site in field scale.

• Journal of Korea Soil Environment Society
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• v.4 no.2
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• pp.77-86
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• 1999

Partitioning of two hydrophobic organic compounds (HOCs), phenanthrene and naphthalene, to kaolinite and sorbed surfactants was studied to evaluate the feasibility of surfactant-enhanced remediation (SER) of contaminated subsurface systems. Sorbed surfactant partition coefficients. $K_ss$, showed a strong dependence on the surfactant sorption isotherms at low sorbed surfactant levels $K_ss$ values were at their highest and then decreased with increasing surfactant sorption densities. $K_ss$ values for SDS were always larger than corresponding $K_mic$values. For Tween 80, however. $K_ss$ values $K_mic$ were higher than $K_mic$ values only at the lower sorbed surfactant densities. HOC distribution between immobile and mobile phases varied with surfactant dose distribution coefficients increased initially with increasing surfactant concentrations and then decreased at higher doses. This observation shows directly the competition between sorbed and micellar surfactants for HOC partitioning. Overall results of this study demonstrate that surfactant sorption to the solid phase can lead to increases in HOC retardation in some SER applications. Therefore, before an SER process is selected, appropriate consideration of surfactant sorption and HOC partitioning to immobile versus mobile phases pertinent to a specific subsurface system must be contemplated.

• Applied Chemistry for Engineering
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• v.22 no.1
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• pp.37-44
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• 2011

The critical micelle concentration (CMC) of sorbitan laurate SP 20 surfactant in this paper was near $7.216{\times}10^{-4}mol/L$ and the surface tension at CMC was about 26.0 mN/m, which showed higher CMC and lower surface tension than those of octylphenol ethoxylate octylphenol ethoxylate (OPE) 10 surfactant. Dynamic surface tension measurement using a maximum bubble pressure tensiometer showed that the adsorption rate at the interface between air and surfactant solution was found to be slower with SP 20 surfactant, presumably due to a low mobility of SP 20 surfactant monomer. The contact angle of SP 20 surfactant solution was observed to decrease with an increase in surfactant concentration and showed a larger value than that of OPE 10 surfactant solution. Half-life time for foams generated with 1 wt% surfactant solution was also larger with SP 20 surfactant, which indicated higher foam stability with SP 20 surfactant. Dynamic behavior study reveals that the solubilization of n-decane oil was much lower with SP 20, which is in good agreement with experimental results of foam stability, contact angle and CMC. Dynamic interfacial tension measurement by a spinning drop tensiometer shows that interfacial tensions at equilibrium condition in both systems were almost the same but the time required to reach equilibrium was longer with SP 20.

• Journal of Microbiology and Biotechnology
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• v.11 no.4
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• pp.716-719
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• 2001

The mobilization and biodegradation of phenanthrene in soil was enhanced by using paraffin oil, which was stabilized by the addition of a surfactant (Brji 30). The ratio of paraffin oil/Brij 30 was determined by measuring the change in the critical micelle concentration. When only surfactant was used, the stabilized paraffin oil emulsion could dissolve more phenanthrene in the water phase. Column experiment showed increased phenanthrene mobilization from the contaminated soil. The phenanthrene mobilized in the paraffine oil/Brij 30 emulsion was biodegraded faster than that in water phase or surfactant solution. This result indicates that a paraffin oil/surfactant system can be effectively used for the removal of PAH from contaminated soil.