Synthesis of a high efficiency DED-12 demulsifier by a simple two-step method

In this paper, a high efficiency DED-12 demulsifier was synthesized using poly (ethylene glycol) diglycidyl ether and ethanolamine as raw materials through a simple two-step method. The DED-12 structure was assessed using both Fourier transform infrared spectrometer and nuclear magnetic resonance hydrogen spectra. Additionally, demulsifying performance of DED-12 was evaluated by bottle test and the effect of concentration, pH value, salinity and temperature on the demulsification efficiency (DE) was studied in detail. The results showed that the DE reached 92.9 % in an emulsion with 70 % water content at 50 ℃ when 300 mg/L of DED-12 was used for 180 min. Especially, it reached 100 % in an emulsion with 30 % water content at 60 ℃. Moreover, DED-12 had good tolerance of acid, alkali and salt. The interfacial competitive adsorption and demulsification mechanism was investigated by the interfacial tension (IFT), three-phase contact angle (CA), zeta potential, coalescence time of droplets (CTD) and optical microscopic observation.