In‐situ monitoring of decane‐in‐water emulsion during microwave irradiation

Microwave (MW)-assisted de-emulsification has been attractive in processes of petroleum production and refining. However, the mechanism and optimal operation remain poorly understood. In this study, the behaviour of decane-in-water emulsion under MW irradiation was monitored in-situ through a size measurement system equipped with the reactor and surface tension profiles. The results indicated that the bubble was formed around the oil droplet during MW irradiation. The MW-induced bubbles can enhance de-emulsification in a similar mechanism as the flotation column. The efficiency of MW de-emulsification depends on emulsion content and MW power. Although a higher MW power is more effective, boiling caused by excessive energy must be considered due to the higher local heating. As a result, moderate power is more desirable. For the decane-in-water emulsions in this study, the optimal condition was determined to be around 500 W.