scholarly journals Mechanism of the intestinal absorption of drugs from oil in water emulsions. V. Enhanced absorption of methyl orange adsorbed at oil/water interface in emulsions.

1975 ◽  
Vol 23 (4) ◽  
pp. 716-724 ◽  
Author(s):  
HIROYASU OGATA ◽  
KIICHIRO KAKEMI ◽  
AKIYUKI FURUYA ◽  
MICHIKO FUJII ◽  
SHOZO MURANISHI ◽  
...  
Keyword(s):  
Methyl Orange ◽  
Intestinal Absorption ◽  
Water Interface ◽  
Enhanced Absorption ◽  
Oil In Water ◽  
Oil Water

scholarly journals Mechanism of the Intestinal Absorption of Drugs from Oil in Water Emulsions. III. Absorption and Biotransformation of Methyl Orange

1972 ◽  
Vol 20 (5) ◽  
pp. 1053-1058 ◽  
Author(s):  
KIICHIRO KAKEMI ◽  
HITOSHI SEZAKI ◽  
HIROYASU OGATA ◽  
CHIEKO NAGAI
Keyword(s):  
Methyl Orange ◽  
Intestinal Absorption ◽  
Oil In Water

Concentration of resveratrol at the oil–water interface of corn oil-in-water emulsions

Adsorption ◽  
2019 ◽  
Vol 25 (4) ◽  
pp. 903-911
Author(s):  
Jolanta Narkiewicz-Michalek ◽  
Marta Szymula ◽  
Sonia Losada-Barreiro ◽  
Carlos Bravo-Diaz
Keyword(s):  
Corn Oil ◽  
Water Interface ◽  
Oil In Water ◽  
Oil Water

OIL SPILL DISPERSION STABILITY AND OIL RE-SURFACING

2008 ◽  
Vol 2008 (1) ◽  
pp. 661-665 ◽  
Author(s):  
Merv Fingas
Keyword(s):  
Water Column ◽  
Oil Spill ◽  
Emulsion Stability ◽  
Dispersed Phase ◽  
Water Interface ◽  
Water Emulsion ◽  
Stabilization Process ◽  
Oil In Water ◽  
Oil Water ◽  
Oil In Water Emulsion

ABSTRACT This paper summarizes the data and the theory of oil-in-water emulsion stability resulting in oil spill dispersion re-surfacing. There is an extensive body of literature on surfactants and interfacial chemistry, including experimental data on emulsion stability. The phenomenon of resurfacing oil is the result of two separate processes: de stabilization of an oil-in-water emulsion and desorption of surfactant from the oil-water interface which leads to further de stabilization. The de stabilization of oil-in-water emulsions such as chemical oil dispersions is a consequence of the fact that no emulsions are thermodynamically stable. Ultimately, natural forces move the emulsions to a stable state, which consists of separated oil and water. What is important is the rate at which this occurs. An emulsion is said to be kinetically stable when significant separation (usually considered to be half or 50% of the dispersed phase) occurs outside of the usable time. There are several forces and processes that result in the destabilization and resurfacing of oil-in-water emulsions such as chemically dispersed oils. These include gravitational forces, surfactant interchange with water and subsequent loss of surfactant to the water column, creaming, coalescence, flocculation, Ostwald ripening, and sedimentation. Gravitational separation is the most important force in the resurfacing of oil droplets from crude oil-in-water emulsions such as dispersions. Droplets in an emulsion tend to move upwards when their density is lower than that of water. Creaming is the de stabilization process that is simply described by the appearance of the starting dispersed phase at the surface. Coalescence is another important de stabilization process. Two droplets that interact as a result of close proximity or collision can form a new larger droplet. The result is to increase the droplet size and the rise rate, resulting in accelerated de stabilization of the emulsion. Studies show that coalescence increases with increasing turbidity as collisions between particles become more frequent. Another important phenomenon when considering the stability of dispersed oil, is the absorption/desorption of surfactant from the oil/water interface. In dilute solutions, much of the surfactant in the dispersed droplets ultimately partitions to the water column and thus is lost to the dispersion process. This paper provides a summary of the processes and data from some experiments relevant to oil spill dispersions.

Pickering-Type Emulsions of ODSA Sizing Agent Stabilized by Nano-Montmorillonite and N-Dodecane

2013 ◽  
Vol 319 ◽  
pp. 233-238 ◽  
Author(s):  
De Hai Yu ◽  
Zhao Yun Lin ◽  
You Ming Li
Keyword(s):  
Particle Concentration ◽  
Ph Value ◽  
Water Interface ◽  
Pickering Emulsions ◽  
Paper Sizing ◽  
Oil In Water ◽  
Effects Of Ph ◽  
Oil Water ◽  
The Stability ◽  
Hydrolysis Resistance

Octadecenylsuccinic anhydride (ODSA) is an internal sizing agent used to hydrophobize paper and paper board in the process of papermaking. Nano-montmorillonite (MMT) particles and n-dodecane were used as the stabilizer to prepare stable ODSA Pickering emulsions. The effects of pH value, particle concentration, hydrolysis resistance and paper sizing performance of the ODSA Pickering emulsions were investigated. It was found that the stability of ODSA emulsions first increased and then decreased as the pH value decreased. More stable oil-in-water (o/w) emulsion can be made using 10 vol.% n-dodecane. Particle concentration was linked to the formation of particle films at oil–water interface, with a required minimum particle concentration of 1.5 wt.%. Paper sizing degree analysis indicated that the ODSA Pickering emulsions show increased hydrolysis resistance and good sizing performance.

scholarly journals Reversible adsorption of proteins at the oil/water interface I. Preferential adsorption of proteins at charged oil/water interfaces

1946 ◽  
Vol 133 (870) ◽  
pp. 121-121
Keyword(s):  
Sodium Chloride ◽  
Isoelectric Point ◽  
Interfacial Area ◽  
Ammonium Bromide ◽  
Water Interface ◽  
Oil Droplets ◽  
Water Emulsion ◽  
Oil In Water ◽  
Alkaline Side ◽  
Oil Water

The behaviour of positively and negatively charged oil-in-water emulsions, stabilized with hexadecyl trimethyl ammonium bromide and sodium hexadecyl sulphate respectively in the presence of protein solutions has been studied. Under certain conditions proteins will adsorb to a charged oil/water interface. When finely dispersed oil-in-water emulsion was used to provide this oil/water interface, adsorption of protein resulted in flocculation of the oil droplets. Flocculation of emulsion on the addition of protein is pH conditioned and occurred on the acid side of the isoelectric point of the protein with negatively charged and on the alkaline side with positively charged oil globules. No flocculation occurred on the alkaline side of the isoelectric point with a negative emulsion or the acid side with a positive emulsion. The amount of protein required to cause maximum clarification of the subnatant fluid corresponded with that needed to give a firmly gelled protein monolayer at the interface, namely, 2∙5 mg. of protein/sq. m. of interfacial area. With that amount of protein the flocculated oil globules remained discrete and no coalescence or liberation of free oil occurred. If only 1 mg. of protein/sq. m. of interfacial area was added, flocculation was followed by rapid coalescence of oil globules and liberation of free oil. If smaller amounts still were used, no visible change in the dispersion of the oil droplets could be seen macroscopically. With greater amounts than 2∙5 mg. /sq. m. of interfacial area, up to ten times the monolayer concentration was adsorbed to the interface. Sodium chloride affected the flocculation range, and instead of the clear-cut change-over between the positive and negative interfaces at the isoelectric point of the protein, overlapping occurred. 5% sodium chloride shifted the flocculation point about 1 unit of pH . The addition of sodium chloride also altered the point of maximum clarification. Thus with haemoglobin the maximum clarification point was shifted from 2∙5 to 1∙7 mg. /sq. m. of interfacial area by the addition of 1% sodium chloride. The adsorption of protein on to charged oil/water interfaces was reversible. This was best demonstrated with haemoglobin. Thus, haemoglobin was adsorbed at pH 5∙0 to a negative emulsion—the red floccules were washed and transferred to a buffer at pH 10. The haemoglobin was released and the emulsion was redispersed. The effect of adsorption and desorption on the structure of the protein molecule has been studied with haemoglobin. By solubility and colour tests it was shown that the haemoglobin molecule was changed to parahaematin by adsorption and subsequent desorption from a charged oil /water interface. Molecular weight and shape determinations were carried out on the desorbed protein. Two proteins have been separated by this adsorption mechanism. This was demonstrated on a mixture of album in and haemoglobin. Some applications of the flocculation technique are indicated and the significance of the phenomena described are discussed.

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