The Stability of Highly Concentrated Water-in-Oil Emulsions and Structure of Highly Porous Polystyrene Produced from Them

Abstract In well stimulation treatments using hydrochloric acid, undesirable water-in-oil emulsion and acid sludge may produce and then cause operational problems in oil field development. The processes intensify in the presence of Fe(III), which are from the corroded surfaces of field equipment and/or iron-bearing minerals of the oil reservoir. In order to understand the reasons of the stability of acid emulsions, acid emulsions were prepared by mixing crude oil emulsion with 15% hydrochloric acid solutions with and without Fe(III) and then separated into free and upper (water free) and intermediate (with water) layers. It is assumed that the oil phase of the free and upper layers contains the compounds which do not participate in the formation of acid emulsions, and the oil phase of the intermediate layers contains components involved in the formation of oil/acid interface. The composition of the oil phase of each layer of the emulsions was studied. It is found that the asphaltenes with a high content of sulfur, oxygen and metals as well the flocculated material of protonated non-polar oil components are concentrated at the oil/acid interface. In addition to the above, in the presence of Fe(III) the Fe(III)-based complexes with polar groups of asphaltenes are formed at the acid/oil interface, contributing to the formation of armor films which enhance the emulsion stability.

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Polarity effects of asphaltene subfractions on the stability and interfacial properties of water-in-model oil emulsions

Fuel ◽

10.1016/j.fuel.2020.117450 ◽

2020 ◽

Vol 269 ◽

pp. 117450 ◽

Cited By ~ 2

Author(s):

Daiwei Liu ◽

Chuanxian Li ◽

Xiaoping Zhang ◽

Fei Yang ◽

Guangyu Sun ◽

...

Keyword(s):

Interfacial Properties ◽

Oil Emulsions ◽

The Stability ◽

Model Oil ◽

Polarity Effects

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Pea Protein for Hempseed Oil Nanoemulsion Stabilization

Molecules ◽

10.3390/molecules24234288 ◽

2019 ◽

Vol 24 (23) ◽

pp. 4288 ◽

Cited By ~ 11

Author(s):

Maciej Jarzębski ◽

Farahnaz Fathordoobady ◽

Yigong Guo ◽

Minghuan Xu ◽

Anika Singh ◽

...

Keyword(s):

Droplet Size ◽

Entrapment Efficiency ◽

Box Behnken Design ◽

Pea Protein ◽

Challenge Tests ◽

Oil Emulsions ◽

The Stability ◽

Potential Food ◽

Potential Use

In this paper, we present the possibility of using pea protein isolates as a stabilizer for hempseed oil (HSO)-based water/oil emulsions in conjunction with lecithin as a co-surfactant. A Box-Behnken design was employed to build polynomial models for optimization of the ultrasonication process to prepare the emulsions. The stability of the system was verified by droplet size measurements using dynamic light scattering (DLS) as well as centrifugation and thermal challenge tests. The z-ave droplet diameters of optimized emulsion were 209 and 207 nm after preparation and 1 week storage, respectively. The concentration of free Linoleic acid (C18:2; n-6) was used for calculation of entrapment efficiency in prepared nanoemulsions. At optimum conditions of the process, up to 98.63% ± 1.95 of entrapment was achieved. FTIR analysis and rheological tests were also performed to evaluate the quality of oil and emulsion, and to verify the close-to-water like behavior of the prepared samples compared to the viscous nature of the original oil. Obtained results confirmed the high impact of lecithin and pea protein concentrations on the emulsion droplet size and homogeneity confirmed by microscopic imaging. The presented results are the first steps towards using hempseed oil-based emulsions as a potential food additive carrier, such as flavor. Furthermore, the good stability of the prepared nanoemulsion gives opportunities for potential use in biomedical and cosmetic applications.

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What Causes the Formation of Water-in-Oil Emulsions?

International Oil Spill Conference Proceedings ◽

10.7901/2169-3358-2001-1-109 ◽

2001 ◽

Vol 2001 (1) ◽

pp. 109-114 ◽

Cited By ~ 3

Author(s):

Mervin F. Fingas ◽

Ben Fieldhouse ◽

James Lane ◽

Joseph V. Mullin

Keyword(s):

Chemical Composition ◽

Shear Rate ◽

Resin Content ◽

Stable Emulsion ◽

Oil Viscosity ◽

The Past ◽

Asphaltene Content ◽

Oil Emulsions ◽

The Stability ◽

Unstable Emulsion

ABSTRACT The results of studies conducted over the past 6 years to characterize why water-in-oil emulsions form are summarized. It is shown that water droplets are held in oil by a combination of viscous and interfacial forces. The stability of an emulsion is very important in understanding its formation because stability is the endpoint or measurement of the entire process. Emulsions can be grouped into three categories: stable, unstable, and mesostable. Each has distinct physical properties. For example, the viscosity of a stable emulsion at a shear rate of I reciprocal second is at least three orders-of-magnitude greater than that of the starting oil. An unstable emulsion usually has a viscosity no more than two orders-of-magnitude greater than that of the starting oil. The zero-shear-rate viscosity is at least six orders-of-magnitude greater than the starting oil for a stable emulsion. For an unstable emulsion, it is usually less than two or three orders-of-magnitude greater than the viscosity of the starting oil. and finally, a stable emulsion has a significant elasticity, whereas an unstable emulsion does not. The stability of emulsions has been studied by examining their asphaltene content and their resin content. Results are reported showing that asphaltenes and resins are responsible for stability. It is noted that, given the correct chemical composition, primarily asphaltenes, sea energy is needed. The properties of the starting oil are the important factor in determining what type of water-in-oil state is produced. Composition and property ranges are given for the starting oil to form each of the water-in-oil states. Important property factors are the asphaltene content, resin content, and starting oil viscosity.

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