Demulsification of Water-in-Crude Oil Emulsions Using Ionic Liquids and Microwave Irradiation

The main objective of this work is to investigate the role of two types of ionic liquids, omimBF(4) and omimPF(6), upon the microwave demulsification process. A series of batch demulsification runs were carried out to evaluate the final emulsified water content of emulsion samples after the exposure to microwaves at distinct ionic liquid concentrations. Tests were performed in a commercial microwave reactor system, using high stable water-in-crude oil emulsion samples containing different salt and water contents. Similar separation tests conducted under conventional heating were investigated for comparisons. Results showed that increasing the concentration of each ionic liquid yields improved demulsification results in both microwave and conventional heating processes. However, the microwave process was always much faster and more efficient than the conventional case. Blank tests without ionic liquid have not produced water separation, which indicates the high stability of the investigated emulsions. In particular, the joint use of omimPF6 (even at low concentrations) and microwave irradiation allows for system demulsification with high efficiency at short time, with some cases even reaching water contents in the range of 1-2% in the final emulsion.