College of Engineering, Department of Chemical Engineering, Qatar University, P.O. Box: 2713, Doha, Qatar.
College of Engineering, Department of Chemical Engineering, Qatar University, P.O. Box: 2713, Doha, Qatar.
Chemosphere. 2022 Mar;291(Pt 3):133099. doi: 10.1016/j.chemosphere.2021.133099. Epub 2021 Nov 27.
The formation of stable emulsions is a fundamental problem in oil industry that can result in a sequence of environmental and operational problems. Chemical demulsification is extensively applied for the recovery of oil from water as well as water from oil. This review introduces different chemical demulsifiers applied for the demulsification and recovery of oil from oil in water (O/W) emulsions. Main types of surfactants (anionic, cationic, nonionics and amphoteric) involved in the formation of emulsions and enhances their stability were discussed. Promising demulsifiers such as nanoparticle (NP), hyperbranched polymers, and ionic liquids (IL), which achieved high oil recovery rate, parameters influencing demulsification efficiency and demulsification mechanisms were explored. Lastly, improvements, challenges, and new changes being made to chemical demulsifiers were underlined. Functionalized magnetic nanoparticles and hyperbranched polymers were very effective in recovering oil from O/W emulsions with an efficiency >95%. Polymers with highly hydrophilic content and high molecular weight can achieve excellent oil recovery rates due to higher interfacial activity, higher dispersion, and presence of specific functional groups. Although ionic liquids could achieve oil recovery up to 90%, high cost limits their applications. NPs showed excellent oil recovery behavior at low concentrations and ambient temperature. Demulsification efficiency of NPs can be enhanced by functionalize with other components (e.g., polymers and surfactants), while service life can be extend by silica coating. Future challenges include scaling up the use of NPs in oil recovery process and highlighting contrasts between lab-scale and field-scale applications.
稳定乳液的形成是石油工业中的一个基本问题，可能会导致一系列环境和操作问题。化学破乳广泛应用于从水中回收油以及从油中回收水。本综述介绍了用于从水包油 (O/W) 乳液中破乳和回收油的不同化学破乳剂。讨论了参与乳液形成并增强其稳定性的主要类型的表面活性剂（阴离子、阳离子、非离子和两性离子）。探讨了纳米颗粒 (NP)、超支化聚合物和离子液体 (IL) 等有前途的破乳剂，它们实现了高采油率、影响破乳效率的参数和破乳机制。最后，强调了化学破乳剂的改进、挑战和新变化。功能化磁性纳米颗粒和超支化聚合物在从 O/W 乳液中回收油方面非常有效，采油率>95%。具有高亲水性含量和高分子量的聚合物由于具有更高的界面活性、更高的分散性和存在特定官能团，因此可以实现优异的采油率。尽管离子液体可以实现高达 90%的采油率，但高成本限制了它们的应用。纳米颗粒在低浓度和环境温度下表现出优异的采油行为。通过与其他成分（例如聚合物和表面活性剂）功能化，可以提高纳米颗粒的破乳效率，通过硅烷涂层可以延长使用寿命。未来的挑战包括扩大纳米颗粒在采油过程中的使用，并突出实验室规模和现场规模应用之间的对比。
