ABSTRACT. Advanced analytical and impact assessment methods are needed for the development of modern surfactants, so the composition, the effect and other properties of surfactants are examined by analytical tools which may be suitable for the quality testing of the raw materials, the intermediates and the final products. The HLB values of non-ionic surfactants and their mixtures were determined by three different methods: theoretical HLB based on the chemical structure and the given HLB of surfactants, the Greenwald method and an improved, titrimetric method. Our aim was to investigate if the new method to determine the water number and HLB value is suitable for this type of commercial surfactants and their mixtures. The particle size and the turbidity of micelles formed in surfactant solutions were also measured and evaluated.

Most petroleum reservoirs are subjected to Improved and Enhanced Oil Recovery (IOR and EOR) processes following secondary recovery. EOR involves the application of external forces and substances to improve the chemical and physical interactions in hydrocarbon reservoirs in order to improve preferable recovery conditions. The process of chemical flooding with solutions of polymers and surfactants can be used for developing oil exploitation. Studying the interaction between surfactants and polymers is indispensable for successful oil recovery. The interaction between non-ionic & anionic surfactants and polymers in ternary mixtures was examined at different concentrations and temperatures by dynamic light scattering and gel permeation chromatography. The hydrodynamic size of surfactant-polymer composites was higher than the particle size of individual components indicating a formation of associates. The size of associates increased by increasing the concentration of the surfactants and the temperature. It could be supposed that the polymer formed a mixed micelle with the surfactants. Gel permeation chromatography has confirmed the increase in molecular weight of the associate formed by surfactants and polymers.

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In the past few decades, considerable researches have been done around the world for increase the oil production; one of the most perspective processes is the chemical enhanced oil recovery. The mixture of polymers and surfactants were used, therefore various surfactant test methods must be developed in order to the surfactant or their mixture would be effective. Surfactant mixtures were prepared and the test methods for their characterization were elaborated for chemical EOR (Enhanced Oil Recovery). The examination of oil flushing effect and emulsifying effect were described. It was found that the surfactants used in EOR should be developed depending on the circumstances of the given area. ÖsszefoglalásAz elmúlt néhány évtizedben világszerte jelentős kutatásokat végeztek kőolajtermelés fokozásával kapcsolatban, az egyik leginkább perspektívikus eljárás a kémiai harmadlagos kőolajkitermelés. Ennek során polimerek és tenzidek keverékét használják fel, ezért a tenzidek fejlesztése során különböző vizsgálati módszereket kell kidolgozni annak érdekében, hogy a tenzid illetve tenzidkeverék hatékony legyen. Kémiai EOR (Enhanced Oil Recovery) célokra állítottunk elő tenzideket illetve tenzidkompozíciókat, melyek jellemzésére laboratóriumi vizsgálati módszereket dolgoztunk ki. Ezek közül az olajkimosóhatás és az emulgeáló hatás vizsgálatát ismertettük. Megállapítottuk, hogy a felhasználandó tenzideket az adott kőolajmező tárolórétegének körülményeihez kell illeszteni.

Non-ionic surfactants are compatible with different types of materials, therefore they can be applied in various packages. Fatty-acid derivates as non-ionic surfactants and their mixtures were investigated to study their colloidal behavior. The HLB value, the particle size, the emulsification capacity and the interfacial tension of various commercial, non-ionic surfactants, and their mixtures with sodium lauryl-ether-sulfate (SLES), were determined. The surfactant mixtures were prepared in different non-ionic: anionic surfactant ratios to examine their effect on several surfactant characteristics. The interfacial tension between the oil phase and aqueous phase was measured using the spinning drop method and the average hydrodynamic diameter of surfactants in the aqueous solution was determined using the dynamic light scattering method. The relationship between various colloidal properties of surfactants was investigated. It was found that there is a significant relationship between the colloidal characteristics and the structure of surfactants that can contribute to their efficient selection method.

The efficiency of demulsification is a key process in terms of extracting the oil of O/V (oil-in-water type) emulsions of enhanced oil recovery. Consequently, the separation of emulsion systems and the recovery of the maximum amount of oil from the colloid system play an important role in the petroleum industry. The stability of the emulsions from oil recovery is influenced by numerous factors. J. L. Salager developed the HLD (Hydrophilic-Lipophilic Deviation) equation in order to examine the efficiency of demulsification. Our aim was to investigate whether the equation developed by Salager is suitable for monitoring the stability of petroleum industrial emulsions.

High-performance emulsifiers and surfactants are used in enhanced oil recovery (EOR). During the polymer-surfactant flooding flow modifier polymer and surfactant are mixed, which reduce the surface tension. It allows to control the mobility and to increase the efficiency of the production. The rheological behaviour of the polymeric, aqueous solutions of surfactants was analysed and their effect on the temperature was studied. The movability of the injected fluid can be predicted by the rheological results which is a significant property for the oil production. Furthermore, informations related to the structure of the polymer-surfactant associates can be obtained by the rheological caracteristics.

In recent decades due to the rapid development of household chemicals and cosmetic industry, the research of surfactants has become increasingly important. Therefore, all type of surfactants has been used in more and more areas. Our aim was to examine if the new titration method can be also suitable for the determination of water number of various surfactants used in petroleum industry and in polymer composites. A correlation analysis was performed with the water numbers measured by the new method. It was found that the solubilty properties can be appropriate for further application.