Influence of Surfactant and Weak-Alkali Concentrations on the Stability of O/W Emulsion in an Alkali-Surfactant–Polymer Compound System

Abstract

Emulsions have emerged as advanced materials for wide industrial applications because of their unique properties. In the actual application in oilfields, emulsions can significantly enhance oil recovery. In the present study, the stability test shows that the concentrations of a surfactant and alkali and salinity have a great influence on the stability of the emulsion, but the addition of excessive chemical agents may adversely affect the emulsion stability. The addition of excessive alkali causes the phase inversion behavior of the emulsion to be discovered, which is also the main reason for the destabilization of the oil-in-water emulsion. Rheological experiments reveal that the emulsion produced by the chemical-flooding fluid is a pseudoplastic fluid, and the apparent viscosity decreases with the increase of the shear rate. Core-flooding experiments were conducted to study the effect of the emulsion stability on enhanced oil recovery, and the results indicate that the system with a better emulsion stability has higher oil recovery and displacement pressure.

Stability, Rheological Behavior, and pH Responsiveness of CTAB/HCl Acidic Emulsion: Experimental Investigation

“…That is, at a shear rate of 250 s –1 , the dependence of viscosity on the concentration of CTAB becomes minor. The pseudoplastic rheological behavior of the emulsion observed at the optimum CTAB amount (i.e., 1 g) may be due to the “micelle solubilization” as explained before by Zhang et al At an amount less than the optimum value, the stability (which is directly related to the rheological behavior) increases steadily due to the increase in the surfactant molecules adsorbed to the interface between the two phases forming the emulsion. However, at a critical surfactant amount (1 g in this case), the surfactant may form micelles that have a solubilization tendency.…”

All-in-one HN@Cu-MOF nanoparticles with enhanced reactive oxygen species generation and GSH depletion for effective tumor treatment

“…49 The previous experiments and research indicated that the HN shell largely prevents drug release from drug-loaded NPs. 26 Thus, HAase was applied in the OH release experiment to degrade HN and release OH. When MB was treated with H 2 O 2 and H 2 O 2 + HAase + HN@Cu-MOF, almost no changes were observed in the absorption of MB in comparison with pure MB solution under the same circumstances (Fig.…”

“…24 Accordingly, Cu 2+ is a frequently applied transition metal in CDT, which can consume the extra GSH generated by tumor cells to produce Cu + , thus carrying out a Fenton-like reaction, increasing oxidative stress in cells and decreasing the clearance of OH. [25][26][27][28] In addition, Cu 2+ is easily oxidized into Cu + in the weakly acidic TEM, which can be approximately 160-times faster than that of Fe 2+ . 29,30 Inspired by this, Cu 2+ -doped MOFs have been designed.…”

Fundamentals and utilization of solid/ liquid phase boundary interactions on functional surfaces

“…LG SL) of the surface towards the two phases: the wetting phase can pass through the porous media and accumulate at the other side, while the non-wetting phase suffers retention [252]. As surfactants reduce interfacial tension, this driving force diminishes with their increasing concentration [256]. Another influencing factors on the effectivity of separation are the drop size of the dispersed phase and the pore diameter.…”