Determining the Dependence of Interfacial Tension on Molecular Area for Phospholipid Monolayers Formed at Silicone Oil–Water and Tricaprylin–Water Interfaces by Vesicle Fusion

Three different macromolecular structures of poly(ethylene oxide-b-propylene oxide) copolymers, used in formulations of commercial demulsifiers for breaking water-in-crude oil emulsions, were investigated. The interfacial activity (), the lower interfacial tension (m), the critical micelle concentration (CMC), the interfacial concentration (Γ) and the molecular area (A) adsorbed at the interface of the surfactant solutions were evaluated. These results were correlated to surfactant performance in coalescing three different asphaltene model emulsions. The PEO-b-PPO commercial demulsifiers, that were capable to dewater asphaltene model emulsions, exhibited interfacial activity to the oil-water interface, reduced the interfacial tension to low values, reached the CMC at low concentration and presented low molecular area adsorbed at the interface.

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Study on the Mechanism of Asphaltenes Reducing Oil-Water Interfacial Tension

Chemical Research in Chinese Universities ◽

10.1007/s40242-021-1178-3 ◽

2021 ◽

Author(s):

Yuwen Wang ◽

Tiexin Cheng ◽

Guangdong Zhou

Keyword(s):

Interfacial Tension ◽

Oil Water

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Mechanism of active silica nanofluids based on interface-regulated effect during spontaneous imbibition

Petroleum Science ◽

10.1007/s12182-020-00537-8 ◽

2021 ◽

Author(s):

Xu-Guang Song ◽

Ming-Wei Zhao ◽

Cai-Li Dai ◽

Xin-Ke Wang ◽

Wen-Jiao Lv

Keyword(s):

Contact Angle ◽

Interfacial Tension ◽

Oil Recovery ◽

Dynamic Contact Angle ◽

Liquid Interface ◽

Spontaneous Imbibition ◽

Wettability Alteration ◽

Low Permeability ◽

Oil Water ◽

Solid Liquid

AbstractThe ultra-low permeability reservoir is regarded as an important energy source for oil and gas resource development and is attracting more and more attention. In this work, the active silica nanofluids were prepared by modified active silica nanoparticles and surfactant BSSB-12. The dispersion stability tests showed that the hydraulic radius of nanofluids was 58.59 nm and the zeta potential was − 48.39 mV. The active nanofluids can simultaneously regulate liquid–liquid interface and solid–liquid interface. The nanofluids can reduce the oil/water interfacial tension (IFT) from 23.5 to 6.7 mN/m, and the oil/water/solid contact angle was altered from 42° to 145°. The spontaneous imbibition tests showed that the oil recovery of 0.1 wt% active nanofluids was 20.5% and 8.5% higher than that of 3 wt% NaCl solution and 0.1 wt% BSSB-12 solution. Finally, the effects of nanofluids on dynamic contact angle, dynamic interfacial tension and moduli were studied from the adsorption behavior of nanofluids at solid–liquid and liquid–liquid interface. The oil detaching and transporting are completed by synergistic effect of wettability alteration and interfacial tension reduction. The findings of this study can help in better understanding of active nanofluids for EOR in ultra-low permeability reservoirs.

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Fabrication of silica/PVA-co-PE nanofiber membrane for oil/water separation

Fashion and Textiles ◽

10.1186/s40691-021-00252-x ◽

2021 ◽

Vol 8 (1) ◽

Author(s):

Yuanli Chen ◽

Hui Fan ◽

Xinlin Zha ◽

Wenwen Wang ◽

Yi Wu ◽

...

Keyword(s):

High Efficiency ◽

Silicone Oil ◽

Hydroxyl Groups ◽

Water Mixture ◽

Silica Nanospheres ◽

Nanofiber Membrane ◽

Water Separation ◽

Oil Water Separation ◽

Silica Nanostructures ◽

Oil Water

AbstractHigh efficiency and anti-pollution oil/water separation membrane has been widely explored and researched. There are a large number of hydroxyl groups on the surface of silica, which has good wettability and can be used for oil-water separation membranes. Hydrophilic silica nanostructures with different morphologies were synthesized by changing templates and contents of trimethylbenzene (TMB). Here, silica nanospheres with radical pores, hollow silica nanospheres and worm-like silica nanotubes were separately sprayed on the PVA-co-PE nanofiber membrane (PM). The abundance of hydroxyl groups and porous structures on PM surfaces enabled the absorption of silica nanospheres through hydrogen bonds. Compared with different silica nanostructures, it was found that the silica/PM exhibited excellent super-hydrophilicity in air and underwater “oil-hating” properties. The PM was mass-produced in our lab through melt-extrusion-phase-separation technique. Therefore, the obtained membranes not only have excellent underwater superoleophobicity but also have a low-cost production. The prepared silica/PM composites were used to separate n-hexane/water, silicone oil/water and peanut oil water mixtures via filtration. As a result, they all exhibited efficient separation of oil/water mixture through gravity-driven filtration.

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Synthesis of aminated polystyrene and its self-assembly with nanoparticles at oil/water interface

e-Polymers ◽

10.1515/epoly-2020-0038 ◽

2020 ◽

Vol 20 (1) ◽

pp. 317-327

Author(s):

Chenliang Shi ◽

Ling Lin ◽

Yukun Yang ◽

Wenjia Luo ◽

Maoqing Deng ◽

...

Keyword(s):

Interfacial Tension ◽

Self Assembly ◽

Carbon Dots ◽

Chain Transfer ◽

Functionalized Polymers ◽

Amino Groups ◽

One Dimensional ◽

Reversible Addition ◽

Oil Water ◽

Chain Transfer Polymerization

AbstractThe influence of density of amino groups, nanoparticles dimension and pH on the interaction between end-functionalized polymers and nanoparticles was extensively investigated in this study. PS–NH2 and H2N–PS–NH2 were prepared using reversible addition–fragmentation chain transfer polymerization and atom transfer radical polymerization. Zero-dimensional carbon dots with sulfonate groups, one-dimensional cellulose nanocrystals with sulfate groups and two-dimensional graphene with sulfonate groups in the aqueous phase were added into the toluene phase containing the aminated PS. The results indicate that aminated PS exhibited the strongest interfacial activity after compounding with sulfonated nanoparticles at a pH of 3. PS ended with two amino groups performed better in reducing the water/toluene interfacial tension than PS ended with only one amino group. The dimension of sulfonated nanoparticles also contributed significantly to the reduction in the water/toluene interfacial tension. The minimal interfacial tension was 4.49 mN/m after compounding PS–NH2 with sulfonated zero-dimensional carbon dots.

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