Application and Synthesis of Gemini Surfactant in Heavy Oil Development.

Gemini surfactants have many potential applications in the viscosity reduction of heavy oils due to their unique structure, which appears to consist of two single-chain surfactant molecules. This paper introduces the viscosity reduction mechanism of gemini surfactants and the research progress of four types of Gemini surfactants used in the viscosity reduction of heavy oils at home and abroad. The study found that in the formation water containing calcium and magnesium ions with a salinity of more than 30000 mg/L, the added amount of gemini anionic surfactant was 0.4-0.5%, the viscosity reduction rate could reach more than 90%, and ultralow interfacial tension (10 orders of magnitude) was achieved. Based on the above advantages, the synthesis and physicochemical properties of gemini anionic surfactants are summarized. Finally, the difficulties in synthesizing anionic gemini surfactants are summarized, and their future development trend is given.