الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
The leakage of crude oil in water resources, including rivers, seas, and oceans become one of the most serious problems found all over the world.
The presence of crude oil in the water resources has several disadvantageous on human and aquatic system. The pollution of aquatic system has a direct influence on the human, plants, animal and air.
The strategy of overcome the presence of crude oil as pollutant in the environment either its removal in case of controlled area polluted by crude oil, or by dispersing the crude oil in case of the uncontrolled area.
Dispersing of crude oil in a wide area of sea or oceans depends on using efficient dispersing agents those can form stable emulsions with crude oil to decrease its concentration in localized area, which prevent the diffusion of oxygen to the undersea aquatic system.
The most famous dispersing agent is the surface active agents or surfactants. Surfactants have the ability to disperse crude oil throughout emulsification process.
The emulsification of crude oil by surfactants has two main problems. The first is the environmental problem caused by the used surfactants, because the efficient surfactants in the emulsification process are mainly non-biodegradable and toxic for aquatic system. and The second is most surfactants lose their emulsifying efficiency in high concentration of salt solutions (as in case of seas or oceans).
To overcome the disadvantages of using surfactants in emulsification of crude oil, several studies were performed to find more efficient emulsifying agents with high stability during their applications in salt water, and also with biodegradable characteristics to prevent the toxic effect on the aquatic system.
In this study, protein was used as emulsifying agent for crude oil in the presence of two surfactants: anionic (sodium dodecyl benzene sulfonate) and nonionic surfactant (Sorbitan mono-fatty acids, Tween20-80).
The influences of different parameters on the stability of the formed surfactants-protein mixtures were studied by determining the surface activities of the emulsifying reagents used including:
1- Effect of concentration.
2- Effect of salinity of the medium.
3- Effect of pH of the medium.
The study of the surface activity of the used anionic, nonionic and protein solutions was performed to determine the surface activity of each compound and the influence of its presence in the crude oil emulsification at different concentration.
The results of the study can be summarized as follows:
1- Tween-80 showed the highest emulsification efficiencyamong thefour typesof Tweens.
2- Anionicsurfactant (Sodium dodecyl benzenesulfonate) showed the highest emulsificationefficiencybetweenthethreestudiedsurface activeagents.
3- Protein showed moderate efficiency during the emulsificationprocessofcrudeoil.
4- Mixing of protein by anionicandnonionicsurfactants affect by variable degree (synergism or antagonism) on the efficiencyof the emulsificationconsiderably.
5- Increasing the salinity ofthemedium up to 80000 ppm has negligibleinfluenceon the emulsificationefficiencyoftheprotein-nonionicsurfactant mixed system.
6- The mixedsystem can beappliedat the entirerangeofpH without considerable change on the emulsification efficiency.
7- The surface andinterfacialactivities of the different mixedsystems have considerable influenceon their emulsification efficiency.
8- In order to formulatehighly efficient emulsifying agents for crudeoil dispersion, the interfacial tension and contact angleof the formulatedemulsifiermustbe at the minimum values.
9-Comparison betweenthedifferentemulsifier’s efficiencies can be performedaccordingto the valuesof their interfacial tension and contact angle at the emulsifiedliquids.
10-Comparison betweenthe emulsifier mixtures depends on the emulsification efficiency and emulsions stability