The interactions between an anionic dye, Acid Green 25 AG and the two cationic surfactants tetradecyltrimethylammonium bromide TTAB, and hexadecyltrimethylammonium bromide CTAB in aqueous solutions far below the CMC are studied using the conductometric method at different temperature. The equilibrium constants and other thermodynamic functions for the process of dye-surfactant ion pair formatio...

The interactions two synthetic triazinyl reactive dyes Mono-s-chloro Triazinyl reactive dyes DI and DII with the cationic surfactant N-hexadecyl pyridinium chloride CPC were studied using a conductometric method in 25, 30, 35, 40 and 45ºC. The equilibrium constants and other thermodynamic parameters for the ion pair formation were calculated on the basis of a theoretical model using the data ob...

The interaction of Congo Red CR with a series of Alkyltrimethylamoniumbromide CnTAB, N-hexadecylpyridinium bromide CPB and N-hexadecylpyridinium CPC were investigated using conductometry technique. It was observed that the formation of dye-surfactant ion pairs takes place at surfactant concentration far below the critical micelle concentration of the individual surfactants. Aggregation was refl...

an ultrasound-assisted surfactant-enhanced emulsification microextra- ction (uaseme) coupled with high performance liquid chromatography-diode array detection has been developed for the extraction and determination of thiopental in serum and urine samples. a simple microextraction method based on emulsification of organic extraction solvent in aqueous sample using an ionic surfactant and withou...

A simple reversed flow injection system with minimal consumption of organic solvent has been developed for the spectrophotometric determination of anionic surfactant (AS) in water samples. The method is based on the ion-pair formation between anionic surfactant and Methylene Blue (MB) and its extraction to chloroform. Sodium dodecyl sulfate (SDS) is used as a model anionic surfactant. The sampl...

fractional flow analysis confirms the advantages of surfactant alternative gas injection (sag) in enhanced oil recovery, but an adsorption phenomenon that has been affected by several factors, weakens the effectiveness of sag injection. in this study, the effects of sacrificial agent, gas phase, and surfactant concentration on adsorption density on silica mineral were investigated by static and...

the ion-pair association constant values, related to the reaction +  were determined by means of the nmr spectroscopy. the values of the thermodynamic functions of the ion pairing process were calculated on the basis of the nmr results. in addition, the association entropy was found to be dependent on the temperature. comparing the experimental data and the fuoss theory it is found that  ion-pa...

the main factor affecting the economics of foam-assisted water alternative gas (fawag) process isthe loss of foaming agent by adsorption onto reservoir rocks. in this study, the effects of phases,surfactant concentration, salinity, adsorbents, and sacrificial agent on adsorption density wereinvestigated by special adsorption experiments. moreover, a series of fawag tests were performedto examin...

The main factor affecting the economics of foam-assisted water alternative gas (FAWAG) process is the loss of foaming agent by adsorption onto reservoir rocks. In this study, the effects of phases, surfactant concentration, salinity, adsorbents, and sacrificial agent on adsorption density were investigated by special adsorption experiments. Moreover, a series of FAWAG tests were performed to ex...

this paper presents efflux time experiments performed in the absence and presence of aqueous solutions of drag reducing agents (dras) when a liquid is emptied from a large open cylindrical storage tank through an exit piping system. the drag reducing agents studied are dodecyl benzene sulfonate anionic surfactant and a mixed solution of surfactant and sodium chloride counter ion. the variables ...