The Formation, Stabilization and Separation of Oil–Water Emulsions: A Review

Abstract

Oil–water emulsions are widely generated in industries, which may facilitate some processes (e.g., transportation of heavy oil, storage of milk, synthesis of chemicals or materials, etc.) or lead to serious upgrading or environmental issues (e.g., pipeline plugging, corrosions to equipment, water pollution, soil pollution, etc.). Herein, the sources, classification, formation, stabilization, and separation of oil–water emulsions are systematically summarized. The roles of different interfacially active materials–especially the fine particles–in stabilizing the emulsions have been discussed. The advanced development of micro force measurement technologies for oil–water emulsion investigation has also been presented. To provide insights for future industrial application, the separation of oil–water emulsions by different methods are summarized, as well as the introduction of some industrial equipment and advanced combined processes. The gaps between some demulsification processes and industrial applications are also touched upon. Finally, the development perspectives of oil–water treatment technology are discussed for the purpose of achieving high-efficiency, energy-saving, and multi-functional treatment. We hope this review could bring forward the challenges and opportunities for future research in the fields of petroleum production, coal production, iron making, and environmental protection, etc.

Antifungal activity of eco-safe nanoemulsions based on Nigella sativa oil against Penicillium verrucosum infecting maize seeds: Biochemical and physiological traits

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Evaluate the effectiveness technology for the treatment of oily wastewater

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“…26 The hydrogen bonding interaction strength is reflected by the peak value of g(r). 48 In our methodology, several RDFs of atom pairs that can form potential H-bonds were evaluated. Herein, we considered hydrogen bonding interactions of (1) aliphatic hydroxyl groups (HO9•••O7 pair), (2) aliphatic and aromatic hydroxyl groups (HO9•••O4 pair), (3) aliphatic hydroxyl groups and water (HO9•••H2O and HO7•••H2O pair), (4) aromatic hydroxyl groups and water (HO4•••H2O pair), and (5) water molecules (H2O•••H2O pair) (Figure 3).…”