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Faruk Nome - One of the best experts on this subject based on the ideXlab platform.
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Zwitterionic Surfactant Stabilized Palladium Nanoparticles as Catalysts in Aromatic Nitro Compound Reductions
Journal of the Brazilian Chemical Society, 2015Co-Authors: Franciane D. Souza, Haidi D. Fiedler, Faruk NomeAbstract:Palladium nanoparticles (NPs) stabilized by ImS3-14, a Zwitterionic Surfactant structurally related to ionic liquids, are revealed here to be good catalysts for the reduction of a large number of substituted aromatic nitro compounds. Our mass spectrometry results are consistent with the formation of amino products in a direct route, where the aromatic nitro compounds are initially reduced to nitroso compounds, which are then reduced to the hydroxylamine derivatives and finally to the anilines. Activation parameters showed that for most Pd catalysts reported in the literature, the mechanism seems to be similar, with lower enthalpy of activation (ΔH ‡ ) being compensated by more negative entropy of activation (ΔS ‡ ). As a result, the reaction is thermally compensated and the rate constants for most reactions rather similar. Furthermore, Pd NPs stabilized by ImS314 showed efficient catalytic activities for the reduction of aromatic nitro compounds, with high conversion and good selectivity even using very low loadings of metal.
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Zwitterionic Surfactant stabilized palladium nanoparticles as catalysts in the hydrogen transfer reductive amination of benzaldehydes
ChemInform, 2014Co-Authors: Emma E Drinkel, Haidi D. Fiedler, Roberta R Campedelli, Alex M Manfredi, Faruk NomeAbstract:Palladium nanoparticles (NPs) stabilized by a Zwitterionic Surfactant are revealed here to be good catalysts for the reductive amination of benzaldehydes using formate salts as hydrogen donors in aqueous isopropanol. In terms of environmental impact and economy, metallic NPs offer several advantages over homogeneous and traditional heterogeneous catalysts. NPs usually display greater activity due to the increased metal surface area and sometimes exhibit enhanced selectivity. Thus, it is possible to use very low loadings of expensive metal. The methodology eliminates the use of a hydrogen gas atmosphere or toxic or expensive reagents. A range of aromatic aldehydes were converted to benzylamines when reacted with primary and secondary amines in the presence of the Pd NPs, which also displayed good activity when supported on alumina. In every case, the Pd NPs could be easily recovered and reused up to three more times, and at the end of the process, the product was metal-free.
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imidazolium based Zwitterionic Surfactant a new amphiphilic pd nanoparticle stabilizing agent
Langmuir, 2012Co-Authors: Bruno S Souza, Elder C Leopoldino, Daniel W Tondo, Jairton Dupont, Faruk NomeAbstract:Palladium nanoparticles (NPs) with an average size of 3.4 nm were prepared in water using imidazolium-based Surfactant 3-(1-dodecyl-3-imidazolio)propanesulfonate (ImS3-12) as a stabilizer. The Pd NPs are highly dispersible in water and chloroform and were characterized by transmission electron microscopy, energy-dispersive X-ray spectroscopy, powder X-ray diffraction, and dynamic light scattering. The results indicate that in water the NP surface is covered with a double layer of ImS3-12 molecules. The NPs were effective in the aqueous biphasic hydrogenation of cyclohexene, with easy recycling and no loss of catalytic activity after four successive runs.
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synthesis of a new Zwitterionic Surfactant containing an imidazolium ring evaluating the chameleon like behavior of Zwitterionic micelles
Langmuir, 2010Co-Authors: Daniel W Tondo, Haidi D. Fiedler, Elder C Leopoldino, Bruno S Souza, Gustavo Amadeu Micke, Ana Carolina Oliveira Costa, Clifford A Bunton, Faruk NomeAbstract:Synthesis of a new Zwitterionic Surfactant containing the imidazolium ring 3-(1-tetradecyl-3-imidazolio)propanesulfonate (ImS3-14) is described. The solubility of ImS3-14 is very low but increases on addition of a salt which helps to stabilize the micellized Surfactant. Fluorescence quenching and electrophoretic evidence for ImS3-14 shows that the micellar aggregation number is only slightly sensitive to added salts, as is the critical micelle concentration, but NaClO4 markedly increases zeta potentials of ImS3-14 in a similar way as in N-tetradecyl-N,N-dimethylammonio-1-propanesulfonate (SB3-14) micelles. The rate of specific hydrogen ion catalyzed hydrolysis of 2-(p-heptoxyphenyl)-1,3-dioxolane and equilibrium protonation of 1-hydroxy-2-naphthoate ion in Zwitterionic micelles of ImS3-14 and SB3-14 are increased markedly by NaClO4 which induces anionoid character and uptake of H3O+, but NaCl is much less effective in this respect. Comparison of ImS3-14 with SB3-14 is based on experimental evidence, and c...
Ajay Mandal - One of the best experts on this subject based on the ideXlab platform.
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core scale modelling and numerical simulation of Zwitterionic Surfactant flooding designing of chemical slug for enhanced oil recovery
Journal of Petroleum Science and Engineering, 2020Co-Authors: Amit Kumar, Ajay MandalAbstract:Abstract Surfactant flooding is a proven enhanced oil recovery method for the recovery of trapped crude oil from the pores of the reservoir. In the present study, the applicability of a synthesized Zwitterionic Surfactant as an efficient EOR agent was tested, in terms of its interfacial tension reduction capability, emulsification behavior, and wettability modification behavior. Core flooding experiments conducted in sandstone core with the injection of 0.3 pore volume of chemical slug after water flooding showed 20% of additional oil recovery. The core flooding experiment was simulated using CMG-STARS simulator and history matching of relative permeability curve and its interpolation parameters were done. The validated model closely represented the experimental core flooding with very low error of 6%. The validated model helps in understanding the movement of crude oil and its interaction with the injected Surfactant slug in the porous media. The validated model was further used for optimization of injected chemical slug by varying the parameters such as the Surfactant concentration in the injected slug, the volume of injected chemical slug, and the injection rate of chemical slug. Each parameter had different effects on the oil recovery efficiency and cumulative oil recovery of more than 90% OOIP was obtained using model with injection of 1 PV of chemical slug containing 100 ppm of Surfactant with the injection rate of 0.3 mL/min. The simulation of core flooding helped in optimization of crude oil production by Zwitterionic Surfactant and its implementation on field scale production by Zwitterionic Surfactant flooding.
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critical investigation of Zwitterionic Surfactant for enhanced oil recovery from both sandstone and carbonate reservoirs adsorption wettability alteration and imbibition studies
Chemical Engineering Science, 2019Co-Authors: Amit Kumar, Ajay MandalAbstract:Abstract Surfactant flooding, a proven method of oil recovery from conventional reservoirs, is limited due to its adsorption on reservoir rocks. Surfactant adsorption leads to modification of wetting state of reservoirs, but it is dependent on the type of Surfactant. In present study, a Zwitterionic Surfactant was selected to study its wettability alteration and adsorption behavior on sandstone and carbonate samples. The adsorption profile was fitted to isotherm models and best-fitted model was determined by R2 values. Zeta potential suggested hydrophilic interaction between the surface and Surfactant. Increase in salinity and alkalinity had opposite effects on Surfactant adsorption. Surfactant was found effective in altering the wetting state of rock surface. Increase in salinity and alkalinity was found to improve the wettability alteration effectiveness. Effective wettability alteration was also tested by spontaneous imbibition into core samples. Thus, Zwitterionic Surfactant was found suitable for application in both sandstone and carbonate reservoirs.
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rsm optimization of oil in water microemulsion stabilized by synthesized Zwitterionic Surfactant and its properties evaluation for application in enhanced oil recovery
Chemical Engineering Research & Design, 2019Co-Authors: Amit Kumar, Rohit Kumar Saw, Ajay MandalAbstract:Abstract Recent advances in formulation and designing of microemulsion with improved viscosity and an ability to reduce interfacial tension, miscibility with oil, have led to their application in enhanced oil recovery (EOR). The physicochemical properties of microemulsion varies widely depending on its composition, stability and temperature. In present study, an investigation has been made to formulate microemulsion using Zwitterionic Surfactant as amphiphile and mineral oil as oleic phase. The optimization of formulation of microemulsion with desired properties was obtained by response surface methodology (RSM). The accuracy and significance of model developed by RSM was tested by analysis of variance (ANOVA) and the model generated was used to analyse the effect of individual components on microemulsion formulation. The optimized microemulsion obtained using RSM was characterized by particle size and zeta potential analysis. The stability and miscibility tests of microemulsion showed excellent results for applicability in chemical EOR. The viscosity of the microemulsion was found to be around 300 mPa S at 10 s−1 shear rate, which is highly encouraging for its application in EOR to improve the mobility ratio. The interfacial reduction and wettability alteration properties of microemulsion was also found to be superior to that of Surfactant solution. The core flooding experiment showed that the optimized microemulsion was able to recover 26.83% of additional oil as compared to 20.01% of oil recovery by Surfactant flooding, over the conventional water flooding.
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synthesis and physiochemical characterization of Zwitterionic Surfactant for application in enhanced oil recovery
Journal of Molecular Liquids, 2017Co-Authors: Amit Kumar, Ajay MandalAbstract:Abstract Surfactant increases recovery of oil from reservoir by decreasing the interfacial tension (IFT) between oleic and aqueous phase and changing wettability of reservoir rock from oil-wet to water-wet. In current work, a carboxybetaine based Zwitterionic Surfactant have been synthesized by quaternization of dodecyldimethylamine with chloroacetate. The synthesized Surfactant has been characterized by FTIR, 1H NMR and TGA analysis. The physicochemical properties of the synthesized Surfactant were measured to check its effectiveness for application in chemical enhanced oil recovery (EOR). The synthesized Surfactant decreased the IFT between crude oil and water from 17 mN/m to 3.77 × 10− 2 mN/m at a low critical micelle concentration (CMC) of 500 ppm. The synthesized Surfactant solution was also effective in changing the wettability of oil wet quartz sample to water wet. Sand pack experiments showed additional oil recovery of 27.03% by flooding of Surfactant slug at CMC. These results evidence the suitability of the synthesized Surfactant for application in chemical EOR.
Rolando Castillo - One of the best experts on this subject based on the ideXlab platform.
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microrheology and characteristic lengths in wormlike micelles made of a Zwitterionic Surfactant and sds in brine
Journal of Physical Chemistry B, 2010Co-Authors: Erick Sarmientogomez, David Lopezdiaz, Rolando CastilloAbstract:We study the Brownian motion of probe particles embedded in a wormlike micellar fluid made of a Zwitterionic Surfactant N-tetradecyl-N,N-dimethyl-3-ammonio-1-propanesulfonate (TDPS), sodium dodecyl sulfate (SDS), and salty water to get structural and dynamical information of the micellar network. The motion of the probe particles was tracked with diffusing wave spectroscopy, and the mean square displacement as a function of time for the particles was obtained. This allowed us to obtain the long-time diffusion coefficient for microspheres moving in the micellar network and the cage size where each particle is harmonically bound at short times in that network. The bulk mechanical susceptibility of the fluid determines the response of the probe particles excited by the thermal stochastic forces. As a consequence, the mean square displacement curves allowed us to calculate the elastic (storage) and the viscous (loss) moduli as a function of the frequency. From these curves, spanning a wide frequency range, we...
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a rheological study in the dilute regime of the worm micelle fluid made of Zwitterionic Surfactant tdps anionic Surfactant sds and brine
Journal of Colloid and Interface Science, 2010Co-Authors: David Lopezdiaz, Erick Sarmientogomez, Cristina Garza, Rolando CastilloAbstract:We present a rheological study for a system made of Zwitterionic Surfactant N-tetradecyl-N,N-dimethyl-3-ammonio-1-propanesulfonate (TDPS), sodium dodecyl sulfate (SDS), and water (0.5 M NaCl). We found that this system forms wormlike micelles. This study is focused in the dilute regime below the overlap concentration, where micelles are not entangled. The overlap concentration was determined using dynamic light scattering. The behavior of the apparent viscosity and the shear stress, both as a function of the shear rate, was determined for different Zwitterionic Surfactant concentrations, temperatures, and two Surfactant ratios (R = [SDS]/[TDPS]). The shear-thickening transition and its temperature dependence was also studied. Finally, we were able to observe the shear-induced structures by using the scattered light from a sheet of light perpendicular to the flow that is installed in the gap of a transparent Couette cell filled with the micellar fluid.
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the wormlike micellar solution made of a Zwitterionic Surfactant tdps an anionic Surfactant sds and brine in the semidilute regime
Journal of Physical Chemistry B, 2010Co-Authors: David Lopezdiaz, Rolando CastilloAbstract:Structural and dynamical properties of a micellar solution are studied mainly through examining its rheological behavior in the semidilute regime. The micellar solution is made of a Zwitterionic Surfactant N-tetradecyl-N,N-dimethyl-3-ammonio-1-propanesulfonate, sodium dodecyl sulfate, and salty water. In particular, we are interested in how the system is affected when the ionic strength of the media is modified by adding salt. Until recently, it was known that this solution forms wormlike micelles. In a range of chemical composition, the solution behaves as a viscoelastic Maxwellian fluid at low frequencies. We present measurements of the elastic (storage) modulus and the viscous (loss) modulus varying the Surfactant ratio (R = [SDS]/[TDPS]), and how the Maxwellian relaxation time abruptly increases when the NaCl concentration is also varied. Reptation and breaking/recombination times were estimated. The effect of temperature in the viscoelastic solution is also studied. Shear stress versus shear rate flo...
Jianxi Zhu - One of the best experts on this subject based on the ideXlab platform.
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development of novel multifunctional adsorbent by effectively hosting both Zwitterionic Surfactant and hydrated ferric oxides in montmorillonite
Science of The Total Environment, 2021Co-Authors: Yixuan Yang, Qingze Chen, Runliang Zhu, Jieqi Xing, Jian Fan, Jianxi ZhuAbstract:Abstract Intercalating various functional species into the interlayer space is an effective strategy to multi-functionalize 2D materials (e.g., montmorillonite, Mnt), but general limitations have emerged therefrom: (1) various intercalated species compete for the limited interlayer space, and (2) the neighboring intercalated species probably inhibit each other's reactivity. Herein, we have synthesized a novel Mnt-based multifunctional adsorbent (HFO-AZ16Mnt) via intercalation of Zwitterionic Surfactant (Z16), acid activation by chloric acid, and introduction of hydrated ferric oxides (HFOs). The acid activation can lead to formation of porous nanosilica, which serves as the new active sites for supporting HFO nanoparticles. Employing tetrachloroferrate (FeCl4−) as an anionic precursor of HFOs can help preserve the sulfonyl group ( SO3−) of Z16 from being electrostatically occupied during the HFO introduction. As a result, HFO-AZ16Mnt can separately and effectively host Z16 and HFOs. The unique structure endows HFO-AZ16Mnt with the efficiency on simultaneous removal of hydrophobic organic contaminants, oxyanions, and heavy metal cations (nitrobenzene, phosphate, and Cd(II), respectively in this study) from water. Particularly, HFO-AZ16Mnt exhibits impressive capacity towards Cd(II) in both the single- (26.1 mg/g) and the multi-contaminant system (30.6 mg/g). This work has demonstrated a new strategy to multi-functionalize Mnt, and provided a promising novel Mnt-based multifunctional adsorbent for simultaneous and effective removal of organic and inorganic contaminants from water.
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novel intercalation mechanism of Zwitterionic Surfactant modified montmorillonites
Applied Clay Science, 2017Co-Authors: Jianxi Zhu, Yanhong Qing, Jingming Wei, Ping Zhang, Ke Wen, Hongmei LiuAbstract:In this present work, a novel intercalation mechanism of Zwitterionic Surfactant modified montmorillonites (ZSMMt) has been introduced. Using 3-(N,N-dimethylpalmityl-ammonio) propane sulfonate (SB16) and montmorillonite (Mt), a series of Zwitterionic Surfactant modified Mt were synthesized. The resulting organoclays were investigated by X-ray diffraction (XRD), Fourier transformed infrared spectroscopy (FTIR), and thermogravimetric (TG) analysis, corroborated by the useful information provided by the element analysis. As revealed by XRD results, the basal spacing of ZSMMt increases from 1.47 nm to 4.13 nm with the increase of Zwitterionic Surfactant loading from 0.2 to 4.0 times of the cation exchange capacity (CEC). According to chemical composition analysis results, the number of Ca2 + ions released during the process of ZSMMt preparation is very limited and the ratios of Ca/Si and Ca/Al of ZSMMt are comparable with those of raw Mt. These results suggest that Ca2 + still remain in the interlayer spaces of Mt. There is no noticeable exchange reaction that takes place between the Zwitterionic Surfactant and the interlayer Ca2 +. After the Zwitterionic Surfactant intercalation, the IR vibration shifts from 1194 to 1191 cm− 1, which implies a new bonding between the Ca2 + and sulfonate group of SB16. The decomposition temperature of the ZSMMt, almost 60–80 °C higher than that of bulk Surfactants, clearly reflects the strong interaction force after intercalation. The present study thus concludes that the intercalation mechanism of ZSMMt is not an exchange process but an ion-dipole interaction between Mt and Zwitterionic Surfactant, thereby, a novel cross-coupling intercalation mechanism of preparing organoclays has been proposed.
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adsorption of phenol and cu ii onto cationic and Zwitterionic Surfactant modified montmorillonite in single and binary systems
Chemical Engineering Journal, 2016Co-Authors: Qingze Chen, Jianxi Zhu, Runliang Zhu, Qi Tao, Godwin A AyokoAbstract:Abstract Organo-montmorillonites (OMts) modified by cationic Surfactant (hexadecyltrimethylammonium bromide, C16) and Zwitterionic Surfactant (hexadecyldimethyl (3-sulphonatopropyl) ammonium, Z16) were used to remove phenol and Cu(II) from aqueous solution. The OMts were characterized by X-ray diffraction (XRD), thermogravimetric analysis (TG), Fourier-transform infrared spectroscopy (FTIR), X-ray fluorescence (XRF), and C, H, and N elemental analyses. Besides the independent adsorption of single contaminants, simultaneous and sequential adsorption of phenol and Cu(II) onto OMts were also investigated. The organic carbon contents of the two OMts were similar but the basal spacing of Z16 modified montmorillonite (Z16-Mt) was larger than that of C16 modified montmorillonite (C16-Mt) indicating a higher packing density of Surfactant and hydrophobicity in C16-Mt with a slight higher adsorption capacity toward phenol. On the other hand, C16-Mt showed much lower capacity in adsorbing Cu(II) as compared with raw montmorillonite. On the contrary, the adsorption capacity of Z16-Mt toward Cu(II) was comparable with that of raw montmorillonite. The equilibrium data of phenol and Cu(II) were fitted satisfactorily with Linear and Langmuir models, respectively. In the sequential adsorption system, the adsorption of one contaminant was not affected by the other pre-adsorbed one; desorption of pre-adsorbed contaminant was also investigated. For both two contaminants, one did not affect the adsorption of the other one onto Z16-Mt and C16-Mt in the simultaneous system. Z16-Mt could rapidly and efficiently remove both phenol and Cu(II) simultaneously. The adsorption kinetics followed the Pseudo-second order model. The results of this work might provide novel information for developing new effective adsorbents toward organic contaminants and heavy metals.
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thermal analysis evidence for the location of Zwitterionic Surfactant on clay minerals
Applied Clay Science, 2015Co-Authors: Jianxi Zhu, Runliang Zhu, Qi Tao, Dong LiuAbstract:Abstract The exact location of Surfactant molecules on clay minerals is critical for the synthesis of clay polymer nanocomposites and their applications in environmental remediation. The location and thermal characteristics of Zwitterionic Surfactant (Z16) composites with montmorillonite (Mt), Al 13 -pillared montmorillonite (AlPMt), calcined AlPMt (AlPMt/500), and talc (Tlc) were investigated by using X-ray diffraction (XRD) and thermogravimetric analysis (TG). The basal spacing of Mt was markedly increased after modification with Z16, while that of Tlc, AlPMt, and AlPMt/500 was essentially unchanged. The decomposition temperature of Z16/Tlc composite (~ 294 °C) was similar to that of the pure Surfactant. Sulfobetaine apparently failed to penetrate into the interlayer space of talc; instead it was confined to external surfaces. On the other hand, the DTG pattern of Z16-modified Mt showed two main peaks (404 and 336 °C), indicating two different intercalation mechanisms of Z16 on Mt. Sulfobetaine, loaded to AlPMt and AlPMt/500, was found to decompose at 355 and 370 °C, respectively, suggesting that Z16 occupied the interpillar space in these samples. Much more Z16 was taken up by AlPMt than by AlPMt/500, although the specific surface areas of both materials were practically identical, suggesting that the Surfactant molecules in the interlayer space of AlPMt were largely adsorbed by electrostatic attraction between the negatively charged groups of Z16 and the positively charged Al 13 cations.
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preparation and characterization of Zwitterionic Surfactant modified montmorillonites
Joint International Conference on Information Sciences, 2011Co-Authors: Jianxi Zhu, Runliang Zhu, Qi Tao, Yanhong Qing, Tong Wang, Jingming Wei, Peng YuanAbstract:Abstract A series of Zwitterionic Surfactant-modified montmorillonites (ZSMMs) were synthesized using montmorillonite and three Zwitterionic Surfactants with different alkyl chain lengths at different concentrations [0.2–4.0 cation exchange capacity (CEC)]. These ZSMMs were characterized by X-ray diffraction (XRD), thermo-gravimetric analysis and differential thermo-gravimetric (TG/DTG) analyses. The Zwitterionic Surfactant could be intercalated into the interlayer spaces of montmorillonites and causing interlayer space-swelling. From XRD measurements, the amount of the Surfactants loaded and the basal spacing increased with Surfactant concentration and alkyl chain length. One endothermic DTG peak occurred at ∼390 °C, which was assigned to the decomposition of the Zwitterionic Surfactant on the organo-montmorillonites from 0.2 to 0.6 CEC. When the Surfactant loading was increased, a new endothermic peak appeared at ∼340 °C. From the microstructures of these ZSMMs, the mechanism of Zwitterionic Surfactant adsorption was proposed. At relatively low loadings of the Zwitterionic Surfactant, most of Surfactants enter the spacing by an ion-exchange mechanism and are adsorbed onto the interlayer cation sites. When the concentration of the Zwitterionic Surfactant exceeds the CEC of montmorillonite, the Surfactant molecules then adhere to the surface-adsorbed Surfactant. Some Surfactants enter the interlayers, whereas the others are attached to the clay surface. When the concentration of Surfactant increases further beyond 2.0 CEC, the Surfactants may occupy the inter-particle space within the house-of-cards aggregate structure.
Willie L Hinze - One of the best experts on this subject based on the ideXlab platform.
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Surfactant mediated cloud point extractions an environmentally benign alternative separation approach
Industrial & Engineering Chemistry Research, 1999Co-Authors: Frank H Quina, Willie L HinzeAbstract:Aqueous solutions of certain Surfactant micelles exhibit phase separation behavior upon temperature alteration. This phenomenon can be exploited in separation science for the development of extraction, purification, and preconcentration schemes for desired analytes. Since the addition of just a small amount of an appropriate nonionic or Zwitterionic Surfactant to the aqueous sample solution is required, this approach is convenient and fairly benign, eliminating the need for the use of organic solvents as in conventional liquid−liquid or solid−liquid extraction. The basic features, experimental protocols, and selected recent applications of this alternative extraction approach, termed cloud point extraction (CPE) or micelle-mediated extraction (ME), are briefly reviewed. In addition, the advantages, limitations, and anticipated future directions of this methodology are discussed.
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concentration of hydrophobic organic compounds and extraction of protein using alkylammoniosulfate Zwitterionic Surfactant mediated phase separations cloud point extractions
Analytical Chemistry, 1991Co-Authors: Tohru Saitoh, Willie L HinzeAbstract:The Zwitterionic Surfactants 3-[nonyl- (or decyl-) dimethyl-ammonio]propyl sulfate, (C9-APSO4 or C10-APSO4) were synthesized using Nilsson's procedure, and their phase separation behavior under different experimental conditions was evaluated. The results indicate that such Zwitterionic Surfactants can be utilized for the extraction/preconcentration of hydro-phobic species in a manner akin to that previously reported for nonionic Surfactants. This was demonstrated for several practical applications including the extraction/preconcentration of some steroidal hormones and vitamin E prior to high-performance liquid chromatography analysis. The Zwitterionic Surfactant mediated phase separation was also applied to the extraction of the hydrophobic membrane protein, bacterio-rhodopsin, from the hydrophilic cytochrome c protein, both originally present in an aqueous phase. The concentration factors for this aqueous two-phase extraction technique using C10-APSO4 ranged from 26 to 35 with recoveries in the range 88 to greater than 96%. Some comparative studies indicate that the use of Zwitterionic Surfactants in lieu of nonionic Surfactants (e.g. polyoxyethylene(7.5) nonyl phenyl ether PONPE-7.5) in such an extraction method offers some significant advantages such as purer, homogeneous Surfactant preparation, minimum background absorbance at UV detection wavelengths, the two-phase region occurring at lower temperatures, and greater extraction efficiencies/concentration factors among others.
