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Abstract Emulsions are widely used in many industrial applications, and the development of efficient techniques for synthesizing them is a subject of ongoing research. Vapor condensation is a promising method for energy‐efficient, high‐throughput production of monodisperse nanoscale emulsions. However, previous studies using this technique are limited to producing small volumes of water‐in‐oil dispersions. In this work, a new method for the continuous synthesis of nanoscale emulsions (water‐in‐oil and oil‐in‐water) is presented by condensing vapor on free‐flowing surfactant solutions. The viability of oil vaporization and condensation is demonstrated under mild heating/cooling using diverse esters, terpenes, aromatic hydrocarbons, and alkanes. By systematically investigating water vapor and oil vapor condensation dynamics on bulk liquid‐surfactant solutions, a rich diversity of outcomes, including floating films, nanoscale drops, and hexagonally packed microdrops is uncovered. It is demonstrated that surfactant concentration impacts oil spreading, self‐emulsification, and such behavior can aid in the emulsification of condensed oil drops. This work represents a critical step toward advancing the vapor condensation method's applications for emulsions and colloidal systems, with broad implications for various fields and the development of new emulsion‐based products and industrial processes.
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Application of magnetic nanoparticles as demulsifiers for surfactant‐enhanced oil recovery
Abstract Nonionic surfactants are increasingly being applied in oil recovery processes due to their stability and low adsorption onto mineral surfaces. However, these surfactants lead to the production of emulsified oil that is extremely stable and difficult to separate by conventional methods. This research characterizes the stability of crude oil mixed with a nonionic surfactant, L24–22, in a brine solution. When subjected to gravity separation, a middle oil‐rich and bottom water‐rich emulsion are generated for various water–oil ratios. Thermal treatments can effectively break oil‐rich emulsions, but the bottom water layer remains contaminated with micron‐sized crude oil droplets. A magnetic nanoparticle treatment is shown to demulsify the crude oil emulsions, dropping the total organic carbon (TOC) in the water layer from 1470 to 30 ppm.
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- Award ID(s):
- 2141112
- PAR ID:
- 10419800
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Journal of Surfactants and Detergents
- Volume:
- 26
- Issue:
- 3
- ISSN:
- 1097-3958
- Format(s):
- Medium: X Size: p. 401-408
- Size(s):
- p. 401-408
- Sponsoring Org:
- National Science Foundation
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