The complicated nature of crude oil emulsions is part of the major setbacks associated with the postulation of methods for phase separation and demulsification in the oil industry. Despite the increasing efforts in generating efficient and dependable demulsification methods, the majority of emulsions cannot be shattered in reduced times. This review examines the trending techniques of crude oil demulsification in the petroleum industry. Several approaches have been examined to discover the best method of demulsification. Hence, this reports reviewed the past studies on the emulsion, formation of oil emulsions, methods of demulsification, characteristics of demulsifier, mechanism of demulsification, kinetics in demulsification, operating parameters influencing the demulsification processes, the structure of demulsifier, and formulations that are involved in the demulsification. The formulations of crude oil demulsification have been investigated to unveil adequate demulsifiers for crude oil. Therefore, demulsification approaches have several applications due to wider varieties of crude oil, separation equipment, brines, chemical demulsifiers, the method in which demulsifiers is been formulated, and product specifications.

Effectively breaking an emulsion is very important in the petroleum industry since the produced crude oil is accompanied by water, which is linked to emulsions and can cause various environmental issues. To resolve these issues, surfactants are combined with crude oil to achieve a stable emulsion. In turn, failure to effectively break the crude oil emulsion can later have both commercial and technical impacts on this industry, mostly in the transportation, refining, and treatment facilities. This review considers some past and current studies on crude oil, the formation and stability of emulsions, the demulsification process and its mechanisms, techniques used to break crude oil emulsions, and formulations of demulsifiers. It demonstrates that combinations of one or more separation modes and demulsification modeling can improve the efficiency of breaking crude oil emulsions.