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1

The modification of filtration properties of porous media using Multizol micellar treatment fluid

Majkrzak Marcin, Falkowicz Sławomir, Stanik Winicjusz

Nafta-Gaz

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2023

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R. 79, nr 9

567--575

EN

The need for the modification of filtration properties of rock media (most frequently porous rocks) appears frequently, e.g., in hydrocarbon exploitation. Exploitation of crude oil and natural gas is frequently accompanied by an excessive and uncontrolled inflow of reservoir water to the production well, which often results in a significant reduction of hydrocarbon production in the late period of reservoir exploitation. The control of water inflow, through modification treatments of rock filtration properties of the near wellbore zone, is the solution to this problem. The use of dedicated treatment fluids is the basis of such success, which, after the injection and change of original physicochemical properties, create local insulation barriers, enabling the control of the flow of fluids in the geological formation. This paper presents the results of the laboratory assessment of the technological effectiveness of Multizol micellar treatment fluid, which is used for selective blocking of the reservoir water inflow to gas wells. Tests performed, at a preliminary stage, comprised the development of a procedure, the obtaining of samples of the treatment fluid, and the performance of flow tests in test glass tubes, which allow for a swift determination of the technological range of the fluid's capability to form gel and emulsion. Flood tests were the main element of testing, related to the measurement of pressure drops of fluids flowing through the sample under the simulated reservoir conditions. The tests were carried out using two types of media, porous rocks (Szydłowiec sandstone) and sand packs. The determination of the modification degree of filtration properties, both in individual zones and in the entire sample/model, was based on the value of the FRR (Residual Resistance Factor) coefficient, being the measure of their permeability reduction. Two types of tests were performed to assess the effect of Multizol treatment fluid on the initial filtration properties of gas and water-bearing zones.

PL

Potrzeba wykonania zabiegów modyfikacji właściwości filtracyjnych ośrodków skalnych (najczęściej skał porowatych) pojawia się często m.in. w pracach związanych z otworową eksploatacją węglowodorów. Wydobyciu ropy naftowej i gazu ziemnego niejednokrotnie towarzyszy nadmierny i niekontrolowany dopływ wody złożowej do odwiertu produkcyjnego, czego bezpośrednim efektem jest (szczególnie w późnym okresie eksploatacji złoża) znaczne ograniczenie produkcji węglowodorów. Kontrola dopływu wody, poprzez zabiegi modyfikacji właściwości filtracyjnych skał strefy przyodwiertowej, stanowi rozwiązanie tego problemu. Podstawą sukcesu tego typu prac jest wykorzystanie specjalnych cieczy zabiegowych, które po zatłoczeniu i zmianie ich pierwotnych właściwości fizykochemicznych miejscowo wytwarzają bariery izolacyjne, umożliwiając kontrolę przepływu płynów w ośrodku geologicznym. W iniejszej publikacji przedstawiono wyniki laboratoryjnej oceny skuteczności technologicznej micelarnej cieczy zabiegowej Multizol, przewidzianej do selektywnego blokowania dopływu wody złożowej do gazowych odwiertów eksploatacyjnych. Przeprowadzone badania, na wstępnym etapie, obejmowały opracowanie procedury i uzyskanie próbek cieczy roboczej oraz realizację tzw. testów płynięcia, które pozwoliły na szybkie określenie technologicznego zakresu zdolności badanej cieczy do tworzenia żelu oraz emulsji. Głównym elementem badań były testy przepływowe, dotyczące pomiaru wielkości spadków ciśnień przepływających przez próbkę płynów, przeprowadzone w symulowanych warunkach złożowych. Badania realizowano z wykorzystaniem dwóch rodzajów ośrodków, rzeczywistych skał porowatych (piaskowiec szydłowiecki) oraz modeli sztucznych warstw/złóż zbudowanych z mieszaniny kulek szklanych i piasku kwarcowego. Określenie stopnia modyfikacji właściwości filtracyjnych, zarówno w poszczególnych strefach, jak i na odcinku całej próbki/modelu, oparto na wartości współczynnika FRR (ang. residual resistance factor) stanowiącej miarę zmniejszenia ich przepuszczalności. Symulację zabiegu ograniczania dopływu wody wykonano dla strefy gazowej oraz zawodnionej.

2

Impact of water content in fuel for smoke opacity

Haller Piotr, Haller Agata, Kaźmierczak Andrzej, Matla Jędrzej, Sroka Zbigniew, Wróbel Radosław

Combustion Engines

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2023

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R. 62, nr 4

123--127

EN

The development of internal combustion engines is focused at solving problems like: fulfilment with increasingly stringent requirements regarding exhaust emissions and elimination of threats to the natural environment. The subject of this thesis is to assess the impact of supplying a compression-ignition engine with hydrocarbon mixtures and to examine the impact of water on external parameters of the engine, such as smoke opacity. The main tests were carried out on a 4-cylinder VW 1.9 TDI internal combustion engine at a constant engine crankshaft speed of 3000 rpm and a variable load of 0, 30, 60, 90, 120, 150 and 180 Nm. The tests were carried out using an innovative mixture of hydrated fusel oils, ethyl alcohol and ionic and/or non-ionic emulsifiers, from which was made of microemulsions with a water content in diesel oil of 5, 10, 15, 20 and 25%. The tests carried out showed a beneficial effect of the water content in the diesel oil on the reduction of the average value of smoke opacity, which systematically decreases with the increase in the percentage of water in the diesel oil.

3

Selected physicochemical properties of water-fuel microemulsion as an alternative fuel for diesel engine

Górska Milena, Bukrejewski Paweł, Stobiecki Jerzy

Archiwum Motoryzacji

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2019

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Vol. 84, nr 2

45--56

EN

The paper focuses on the assessment of selected physicochemical properties of microemulsion containing 5% by mass (m/m) of surface active compounds (SAC), i.e. Span20 and Crilet4 as well as 10% (m/m) of distilled water dispersed in diesel fuel (DF). In particular temperature dependent properties such as: flash point (FP) and cold filter plugging point (CFPP) as well as lubricity, friction coefficient, corrosiveness and kinematic viscosity of tested fuels were examined. It was found that the tested surfactants and water added to DF increase microemulsion FP by 13ºC. For this reason, it can be stated that tested microemulsion is safer than typical DF. On the other hand it was found that the CFPP of the tested microemulsion is also adequately higher. It means less usefulness of such fuel during winter periods. Based on the research results it can be stated that addition of tested surfactants slightly worsens the lubricity of DF. However, the same surfactants in the presence of dispersed water reduce the friction in the tribological node and improve the lubricity of the tested microemulsion. Research showed that tested microemulsion system is not corrosive as well as its kinematic viscosity meet requirements of EN590 standard. Based on all these findings, microemulsion is considered as safe and such fuel can be recommended for engine tests without the risk of its damage.

4

Statistical Optimization of the Preparation of HNIW Nanoparticles via Oil in Water Microemulsions

Bayat Y., Zarandi M., Khadiv-Parsi P., Salimi Beni A.

Central European Journal of Energetic Materials

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2015

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Vol. 12, no. 3

459--472

EN

HNIW (2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaazaisowurtzitane) is a family member of high-energy density cage nitramines which have so many versatile applications. In this paper, HNIW nanoparticles were prepared by the oil in water microemulsion route. The effects of various experimental parameters on this reaction were investigated using the Taguchi method. The effects of different variables: organic phase, water/organic phase (W1/W2), organic phase/ propanol (W3/W4) and HNIW weight percent, on the particle size of the HNIW were investigated at three distinct levels. Optimal conditions for obtaining HNIW nanoparticles were determined. Performing the process under the optimal conditions proposed by the Taguchi method leads to the production of HNIW nanoparticles with an average size of about 80 nm. The HNIW nanoparticles were characterized using Scanning Electron Microscopy (SEM), Dynamic Light Scattering (DLS), Differential Thermal Analysis (DTA) and X-Ray Diffraction (XRD).

5

Flotation after a direct contact of flotation reagents with carbonate particles. Part 1, Model investigations

Ahmed H. A. M., Aljuhani M. S., Drzymala J.

Physicochemical Problems of Mineral Processing

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2013

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Vol. 49, iss. 2

713--723

EN

Carbonate fluorapatite (francolite), calcite and dolomite separately, as well as their model mixtures, were subjected to flotation after conditioning the particles with microemulsion consisting of 20% of Custafloat AR27 (collector, blend of fatty acid soaps and sulfates), 55% fuel oil #5 and 25% water at 70% solids density and subsequent pulp dilution with water to 25% solids. The best separation of carbonate fluorapatite from calcite and dolomite occurred at pH 8.5 and microemulsion dose between 0.9 and 1.5 kg/Mg, 1.5 min conditioning time and 2 minutes of flotation time. The obtained flotation concentrates using 1.5 kg/Mg of collector contained 84% carbonate fluorapatite (34% P2O5) with 84% recovery. The 84/84 separation efficiency in terms of grade-recovery indices points to promising results which can be obtained for real phosphate ores.

6

Water - fuel microemulsions influence on fuel consumption and exhaust gas emissions

Cienciała M., Haller P., Jankowski A., Kardasz P.

Journal of KONES

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2013

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Vol. 20, No. 3

111--116

EN

Combustion in a diesel engine is a complex physicochemical process, changing the time at which the events take place simultaneously heat and mass transfer and chemical reactions. The development of internal combustion engines goes towards meeting the increasingly stringent requirements for toxic exhaust emissions, reducing fuel consumption and therefore reduce carbon emissions and protect the Earth's natural resources. The problem to solve in modern combustion engines is the emission of NOx. One way to reduce the emission of toxic NOx combustion engine power is water-hydrocarbon emulsions [1]. Research combustion engines water-hydrocarbon emulsions has been its tradition. So far, attempts were carried out using an emulsion obtained by a chemical. Emulsions of oil and water can be obtained by adding various detergents to prevent delamination of the oil and water. In this article, we consider the possibility of applying a mixture of water and oil as an alternative fuel used to power internal combustion engines used in heavy road transport. This work is preliminary work, also having to check whether this is the future direction of the work. The measurements of emissions of exhaust gases and fuel consumption. After analysing the test results confirmed that the improvement of the economic and environmental performance of modern diesel engines, it can be achieved by supplying synthetic diesel or gas oil water emulsions. It was found that the use of emulsion leads to a reduction of fuel consumption and NOx emissions.

7

Structural and Optical Characterization of ZnO Nanoparticles Synthesized by Microemulsion Route

Kumar H., Rani R.

International Letters of Chemistry, Physics and Astronomy

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2013

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Vol. 14

26--36

EN

ZnO nanoparticles were synthesized by microemulsion route in W/S ratio of 5 at room temperature. X-ray diffraction (XRD) pattern reveals wurtzite structure of ZnO nanoparticles. Rod shape of ZnO nanoparticles of average particle size 10.0 to 12.0 nm were observed by transmission electron microscopy. FT-IR spectra confirmed the adsorption of surfactant molecules at the surface of ZnO nanoparticles and presence of Zn-O bonding. Thermal studies were carried out by the differential scanning calorimeter (DSC) techniques. In addition, UV-Visible spectra were employed to estimate the band gap energy of ZnO nanoparticles.

8

Rheological investigations of pharmaceutical emulsions prepared with modified lecithin

Rosa M., Kwiecień M., Tal-Figiel B.

Czasopismo Techniczne. Chemia

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2013

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R. 110, z. 1-Ch

69--77

EN

In this paper the results of rheological investigations of pharmaceutical microemulsions prepared using modern lecithine derived emulsifiers has been prevented out. High stability of obtained systems and wide possibilities of controlling rheological parameters were found.

PL

W artykule przedstawiono wyniki badań reologicznych mikroemulsji farmaceutycznych, sporządzonych z wykorzystaniem nowoczesnych emulgatorów na bazie lecytyny. Stwierdzono wysoką stabilność tych układów oraz duże możliwości regulowania właściwości reologicznych.

9

Porównanie ilościowego oznaczania octanu α-tokoferolu w preparatach farmaceutycznych metodą mikroemulsyjnej chromatografii elektrokinetycznej oraz ultraszybkiej chromatografii cieczowej

Wideł D., Oszczudłowski J., Witkiewicz Z., Moczulski M.

Chemik

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2013

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Vol. 67, nr 2

111-118

PL

W artykule opisano zastosowanie mikroemulsyjnej chromatografii elektrokinetycznej (MEEKC) do ilościowego oznaczania witaminy E w postaci octanu α-tokoferolu. Analizę wykonano za pomocą aparatury do elektroforezy kapilarnej, zaopatrzonej w detektor z matrycą diodową. W kapilarze stosowano mikroemulsję o składzie: 10% (w/w) SDS, 6,6% (w/w) 1-butanolu, 0,8% (w/w) n-oktanu, 12,5% (w/w) 2-propanolu, 40% (w/w) buforu fosforanowego o pH=2,5 oraz 30,1% (w/w) wody demineralizowanej. Oznaczanie ilościowe witaminy E wykonano metodą wzorca zewnętrznego z wykorzystaniem oprogramowania 32 Karat ver. 8.0 Beckman Coulter Inc. Dodatkowo wykonano oznaczanie ilościowe witaminy E metodą ultraszybkiej chromatografii cieczowej (UFLC) w celu porównania wyników z metodą MEEKC.

EN

In the present work microemulsion electrokinetic chromatography (MEEKC) was applied for quantitative determination of vitamin E in α-tocopherol acetate form. Capillary electrophoresis system with diode array detector was used to perform the analysis. Microemulsion consists of: 10 % (w/w) SDS, 6.6 % (w/w) 1-butanol, 0.8 % (w/w) n-octane, 12.5 % (w/w) 2-propanol, 40% (w/w) phosphate buffer with pH=2.5 and 30.1 % (w/w) demineralized water, was used in capillary. The quantitative determination of vitamin E was performed with the external standard method with the use of the 32 Carat ver. 8.0 software from Beckman Coulter Inc. Additionally the quantitative determination of the vitamin E by ultrafast liquid chromatography (UFLC) method was performed for the purpose of the comparison of results with the MEEKC method.

10

Zastosowanie mikroemulsji jako składnika poprawiającego sprawność płynów szczelinujących i odbiór cieczy po wykonanym zabiegu

Czupski M.

Nafta-Gaz

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2012

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R. 68, nr 3

171-179

PL

Bardzo ważnym czynnikiem mającym wpływ na powodzenie zabiegu hydraulicznego szczelinowania skał zbiornikowych jest sprawność płynu, która z kolei zależy od jego filtracji do złoża. Kluczowe znaczenie ma także oczyszczenie strefy dookoła wytworzonej szczeliny, jak również samej warstwy podsadzki. W tym celu do płynów szczelinujących dodawane są środki powierzchniowo czynne, których zadaniem jest redukcja napięcia powierzchniowego i kąta zwilżania oraz kontrola filtracji. Od około dekady z powodzeniem stosowane są również mikroemulsje, które stanowią mieszaninę środka powierzchniowo czynnego, rozpuszczalnika/ropy/współrozpuszczalnika i wody. Dlatego w niniejszym artykule zaprezentowano badania, które miały na celu sprawdzenie wpływu, jaki na właściwości cieczy szczelinujących będzie miało zastosowanie w ich składzie dostępnych na rynku mikroemulsji, w porównaniu do konwencjonalnego środka powierzchniowo czynnego.

EN

Fracturing fluid efficiency is a very important factor which has a crucial impact on the success of hydraulic fracturing treatment. This fluid efficiency depends on the leakoff. Then, cleanup of the area around the fractured proppant pack and propped fracture is also very important. Therefore surfactants are used in hydraulic fracturing fluids to reduce surface tension, contact angle and leakoff control. For about a decade microemulsions have also been used successfully. They are defined as a mixture of surfactant, solvent/oil/co-solvent and water. So this paper describes laboratory studies, which illustrate how the application of the microemulsions affects the fracturing fluid properties, in comparison to a conventional surfactant.

11

Biopłyny mikroemulsyjne

Kaźmierczak U., Kulczycki A.

Journal of KONBiN

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2012

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No. 1 (21)

141--148

PL

Wprowadzanie biopaliw w miejsce olejów opałowych oraz biokomponentów do olejów opałowych napotyka na wiele trudności technologicznych i technicznych. Produkt końcowy, którym ma być biopłyn mikroemulsyjny musi posiadać w swoim składzie nie tylko odpowiednio dobrany pakiet emulgatorów mających właściwość utrzymania stałej liczby HLB, odpornej na zmienność tworzących go składników, ale także opracowanie takiej metody wytwarzania biopłynu mikroemulsyjnego, który będzie stabilny w określonej temperaturze, w określonym przedziale czasowym, oraz musi zostać wytworzony w warunkach maksymalnie zbliżonych do produkcji przemysłowej. W publikacji przedstawiono wstępne wyniki badań z zastosowaniem ciekłych odpadów z przemysłu mleczarskiego oraz analizę ekonomiczną odniesioną do stosowania mikroemulsyjnych biopłynów zasilających lokalne źródła energii elektrycznej uzupełniające potrzeby sieci energetycznych.

EN

Introduction of biofuels in place of heating oils and biocomponents of heating oils is fraught with technological and technical difficulties. The final product - microemulsion bioliquid must have in its composition more appropriately selected emulsifiers package designed to maintain a constant characteristic HLB resistant to variation of bioliquid components. Final microemulsion bioliquid should be stable at a wide range of temperature, the certain period of time, and should be produced under conditions easy to apply in industry. The paper presents preliminary results focused on liquid waste from dairy industry using as microemulsion bioliquid component and an economic analysis of microemulsion bioliquids application in supplying of electricity to local grids accordingly to their needs.

12

Ekstrakcja białek przy użyciu odwróconych miceli

Matla M., Smętek A., Pyć R.

Biotechnology and Food Science

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2011

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Vol. 75, nr 1

97-108

PL

Odwrócone micele, czyli mikroemulsje typu woda w oleju są trójskładnikowymi systemami, które składają się z wody, cząsteczek surfaktantu i rozpuszczalnika organicznego. Mogą one być wykorzystywane do ekstrakcji w układzie ciecz-ciecz celem oczyszczania i wydobywania białek i innych cząsteczek. Odwrócone micele są atrakcyjnymi narzędziami w biotechnologii, ponieważ ekstrakcja w tych systemach jest tania, wydajna i łatwo jest w niej powiększać skalę. Wydajność ekstrakcji białek i ich rozpuszczanie w odwróconych micelach zależy od wielu czynników, takich jak pH, siła jonowa czy rodzaj i stężenie surfaktantu. W poniższym artykule przedstawiono proces ekstrakcji białek w odwróconych micelach i ich potencjalne zastosowania. Określono także i omówiono czynniki, które wywierają wpływ na ekstrakcję w układzie ciecz-ciecz.

EN

Reversed micelles, or water-in-oil microemulsions are three-component systems, that consist water, surfactant molecules and organic solvent. They can be used for liquid-liquid extraction to purificate and recovery proteins and other molecules. Reversed micelles are attractive tools for biotechnology because extraction in this systems is cheap, efficient and easy to scale up. Efficiency of protein extraction and solubilization in reversed micelles depends on many factors like pH, ionic strength, surfactant type and concentration. The present review describes the process of protein extraction in reversed micellar systems and shows potential applications of it. It also specify and describe factors that affect liquid-liquid extraction.

13

Preparation of ag/cu-doped titanium (iv) oxide nanoparticles in w/o microemulsion

Zielińska-Jurek A., Walicka M., Tadajewska A., Łącka I., Gazda M., Zaleska A.

Physicochemical Problems of Mineral Processing

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2010

|

Vol. 45

113-126

EN

The Cu-TiO2 and Ag/Cu-TiO2 nanoparticles have been prepared using a water-in-oil microemulsion system of water/AOT/cyclohexane. The photocatalytic activity of the catalysts was estimated by measuring the decomposition rate of phenol in 0.21 mM aqueous solution under visible light irradiation. The bioactivity of Ag/Cu-doped titanium (IV) oxide nanocomposites was estimated using bacteria Escherichia coli and Staphylococcus aureus, yeast Saccharomyces cerevisiae and pathogenic fungi belonging to Candida family. The photocatalysts' characteristics by X-ray diffraction, BET surface area measurements, Scanning Electron Microscopy (SEM) energy dispersive spectroscopy (EDS) analysis showed that a sample with the highest photo- and bioactivity had anatase structure, about 190 m2/g specific surface area, absorbed light for ?>400 nm and contained 1.45 mass % of silver, 1.40 mass % of copper and 59.4 mass % of Ti.

14

Preparation and characterization of SiO2 microspheres doped with CoFe2O4 nanocrystals

Tyrpekl V., Poltierová-Vejpravová J., Plocek J., Nižňanský D.

Materials Science Poland

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2010

|

Vol. 28, No. 1

129--137

EN

Main goal of the reported work was to fabricate silica microspheres doped with magnetic nanocrystals. Cobalt ferrite nanocrystals were fabricated separately via surfactant-assisted coprecipitation. The sol-gel method in microemulsion was subsequently used for encapsulating of the magnetic nanonanocrystals into the silica microspheres. Final products were characterized by various techniques and magnetic measurements. The obtained silica microspeheres doped with CoFe2O4 were of average diameter 11 žm.

15

Wytwarzanie nanocząstek BaSO4 w mikroemulsjach

Podgórska W., Jezierska E.

Inżynieria i Aparatura Chemiczna

|

2010

|

Nr 2

99-100

PL

Praca dotyczy produkcji cząstek BaSO4 w mikroemulsji w/o. Do wytworzenia mikroemulsji zastosowano niejonowy surfaktant Marlipar 13/40 finny Sasol. Proces prowadzono w sposób okresowy w reaktorze o średnicy O, 1 m zaopatrzonym w mieszadło Rushtona (D = T72). Uzyskane kryształy mają rozmiary od kilku do kilkunastu nanometrów i charakteryzują się wąskim rozkładem wielkości. Wielkość kryształów maleje ze wzrostem częstości obrotów mieszadła, wzrostem stężenia reagentów i wzrostem stosunku stężeń.

EN

The present work considers precipitation of BaSO4 crystals in w/o micro emulsion. Microemulsion was produced using nonionic surfactant Mar lipar 13/40. The precipitation process was carried out in a batch reacto; (T= 0.1 m, Rushton turbine D = T72). A size of produced crystals was in thf range between few and several nanometers and particle size distribution waf narrow. The crystal size decreased generally with the increase in impellei speed, as well as with the increase in concentration and concentration ratic of reagents.

16

Preparation of Silver Nanoparticles in Reverse Micelles and Antibacterial Activity of Silver Modified-Paints

Reszczyńska J., Zieliński A., Łącka I., Skwarek E., Zaleska A.

Advances in Materials Science

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2010

|

Vol. 10, nr 4(26)

12-20

EN

Silver particles having fine or ultrafine sizes are one of the fastest growing research interests with wide applications. Here we report the preparation method of silver modified paints which revealed antimicrobial activity against gram-negative bacteria Escherichia coli, gram-positive Staphylococcus aureus, yeast Saccharomyces cerevisiae and pathogenic fungi belonging to Candida family. In this work, we choose heptane and cyclohexane, as the oil phase for preparation nanometer sized metallic particles. We have also studied the effect of different silver precursors – silver nitrate, silver citrate and different surfactants: anionic AOT, non-ionic Triton X100, Span 80 and Tween 85 for stabilization of obtained silver colloids. UV-VIS spectrum contained a strong plasmon band near 410 nm, which confirmed silver ions reduction to Ag° in microemulsion system or aqueous phases. Prepared samples contained from 500 to 2000 ppm of silver. The diameter size of silver nanoparticles was in the range from 16 nm to 82 nm and were stable for 3 months without precipitation.

17

Studies on the Interfacial Composition, Thermodynamic Properties and Structural Parameters of W/O Microemulsions Containing Surfactant-like Ionic Liquid

Li Y., Chai J. -L., Xue X. -N., Zhang Z. -M.

Polish Journal of Chemistry

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2009

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Vol. 83, nr 10

1809-1820

EN

The interfacial composition, ther mo dy namic prop er ties and struc ture pa ram e ters of the microemulsion systems con tain ing surfactant-like ionic liquid have been investigated with the dilution method of the W/O microemulsions. The interfacial parameters of Xa i , thermodynamic properties K, –Delta Go i o rghtwards arrow and structure parameters Re, Rw, Nd, Ns, Na have been calculated and discussed for microemulsion systems surfactant-like ionic liquid C12mimBr (C14mimBr, C16mimBr) / alcohol / alkane / water. The effects of water content, alcohols, alkanes, salinity and temperature on above parameters were dis cussed. The results show that with the in crease insalinity and the carbon chain length of both surfactant and alcohol, or with the decrease in the carbon chain length of the alkanes, the molar fraction of the alcohol at the interfacial layer (Xa i ) decreases, the formation of the micro - emulsion is more spontaneous in thermodynamics, and the droplets of the W/O microemulsion were enlarged. The size of the microemulsion droplets is sensitive to the water content, and increases significantly with increasing water content.

18

Effects of Short-chain Alcohols on the Phase Behavior, Solubilities and Solubilization Ability in Microemulsion Systems

Xia Y., Li H. L., Chai J. L., Yu X. Y., Liu J., Qin C. K., Chen J. F.

Polish Journal of Chemistry

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2009

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Vol. 83, nr 2

315-324

EN

The effects of short-chain alcohols on the phase behavior, solubilities and solubilization ability in the microemulsion systems cetyltrimethyl ammonium bromide (CTAB) or cetylpyridinium bromide (CPB) or 1-hexadecyl-3-methylimidazolium bromide (C16mimBr)/1-propanol or 1-butanol or 1-pentanol/n-octane/brine were investigated with the d-g fishlike phase diagram. The phase diagram was affected greatly by alcohols, and the magnitude of the middle phase region in the fish body is in the order 1-propanol greated than greated than 1-butanol greated than1-pentanol. With the carbon chain length becoming shorter, more alcohol molecules are needed to balance the interfacial layer. Nearly all surfactants enter into the interfacial layer and little remains in aqueous or oleic phase. However, alcohols dissolve in the aqueous and oleic phases, besides they enter into the interfacial layer. The solubilization ability of the microemulsion system is mainly affected by the alcohols and the order is 1-pentanol greated than 1-butanol greated than 1-propanol.

19

The Electrochemical Oxidation of Selected Antioxidants at a Glassy Carbon Electrode in Microemulsions

Szymula M., Narkiewicz-Michałek N.

Polish Journal of Chemistry

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2008

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Vol. 82, nr 1-2

121-129

EN

The electrochemical oxidation of three antioxidants of various hydrophilic/hydrophobic characters in microemulsions stabilized by the anionic surfactant SDS was investigated using the cyclic voltammetry method. It was found that in microemulsions the oxidation process ismore difficult than in electrolyte solutions. The oxidation potential (Epa) of hydrophobic antioxidants propyl gallate (PG) and alfa-tocopherol (alfa-T) at a glassy carbon electrode increases monotonically with the decrease of water content, whereas for the ascorbic acid (AA) the peak potential behaviour is more complicated. At first, Epa increases with the decreasing oil content up to the bicontinuous phase composition and then decreases rapidly. The currents (Ipa) for hydrophobic antioxidants are low in the whole composition range of microemulsion. For hydrophilic AA, Ipa is much higher, especially in the oil-in-water system. In the paper the changes of redox parameters of selected antioxidants are related to the micro-heterogeneity of the colloidal system and the structure of the adsorption layer formed on the electrode surface.

20

Phase Behavior and Solubilization of Microemulsion System Formed by Aliphatic Polyethenoxy Ether and Sodium Dodecyl Sulfonate

Chen J. F., Gao Y. Ch., Li H. L., Chai J. L., Yang X. D., Qin C. K.

Polish Journal of Chemistry

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2008

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Vol. 82, nr 5

1067-1076

EN

The phase behavior and solubilization of the quaternary system AEO-9/AS/n- butanol /alkane/NaCl solution were investigated with delta-gamma and epsilon-beta fishlike phase diagrams. Two kinds of diagrams were plotted and compared in their shapes, HLB plane equations and solubilization power representations. Their HLB plane equations were used to calculate the composition of the hydrophile-lipophile balanced interfacial layer. It is found that the synergism between AEO-9 and AS in the inter facial layer in solubilization power exists. The influences of oil and aqueous medium on the epsilon-beta fishlike phase diagram were also discussed.