High density of heavy oils is connected also with high

The mixture of two block copolymers RPE 3110 and PE 6100 which have similar P276-00 block content (polyethylene oxide, %) and similar hydrophobic block content (polypropylene oxide, %) but their structure are different (PPO-PEO-PPO and PEO-PPO-PEO). Due to their amphiphilic structure the block copolymers have the high interfacial activity to the oil–water interface. The PEO segment is more hydrophilic and interacts preferably to the water molecules and the PPO segment is more lipophilic and mainly interacts with the oil phase. The mixture of two demulsifiers provides the extensive adsorption of the demulsifier molecules. The more hydrophilic part of the demulsifiers interacts with the water molecules and decreases the interaction between the stabilizer molecules and the water molecules [4]. The hydrophobic part of the demulsifiers (polypropylene oxide blocks) is oriented to the depth of the oil phase. The oil phase spontaneously penetrates on the vacancies at the interface and the stabilizer particles wetted by the oil are displaced from the interface into the oil phase. The water globules are deprived of the protective layers. As a result of the collision of dispersion phase particles water droplets can coalesce into larger ones.