A review study on new aspects of biodemulsifiers: Production, features and their application in wastewater treatment. (December 2021)

• Record Type: Journal Article
• Authors: Yao, Lei; Selmi, Abdellatif; Esmaeili, Hossein
• Is Part Of: Chemosphere. Volume 284(2021)
• Publication Date: 2021-12
• Subjects: Biodemulsification -- Biosurfactant -- Biodemulsifier -- Microorganism -- Oil/water emulsion; Pollution -- Periodicals; Pollution -- Physiological effect -- Periodicals; Environmental sciences -- Periodicals; Atmospheric chemistry -- Periodicals; 551.511
• DOI: 10.1016/j.chemosphere.2021.131364
• Languages: English
• ISSNs: 0045-6535

Abstract

Abstract: The effluent produced in refineries is in the form of an oil/water emulsion that must be treated. These emulsions are often stable and a suitable method must be used to separate the oil from the emulsion. Recently, biosurfactants or biodemulsifiers have received much attention to reduce the interfacial tension between two liquids. Biodemulsifiers are produced by microorganisms and have several benefits over chemical demulsifiers such as low-toxic, biodegradability, eco-friendly and easy synthesis. They can eliminate two phases by changing the interfacial forces between the water and oil molecules. Biosurfactants are categorized based on the molecular weight of their compounds (low or high molecular weight). Sophorolipids, lipopeptides rhamnolipids, trehalolipids, glycolipid, lipoproteins, lichenysin, surfactin, and polymeric biosurfactants are several types of biosurfactants, which are produced by bacteria or fungi. This review study provides a deep evaluation of biosurfactants in the demulsification process. To this end, different types of biosurfactants, the synthesis method of various biosurfactants using various microorganisms, features of biosurfactants, and the role of biodemulsifiers in the demulsification process are thoroughly discussed. Also, the impact of various efficient factors like pH, microorganism type, temperature, the oil content in the emulsion, and gravity on biodemulsificaion was studied. Finally, the mechanism of the demulsification process was discussed. According to previous studies, rhamnolipid biodemulsifier showed the highest biodemulsification efficiency (100%) in the removal of oil from an emulsion. Graphical abstract: Image 1 Highlights: Biodemulsifiers can be used to remove oil molecules from O/W emulsions. Biodemulsifiers can be produced by microorganisms such as fungi and bacteria. Different types of biosurfactants, synthesis methods, features and their mechanism were studied. The impact of pH, microorganism type, temperature, and oil content on demulsificaion was studied.