Search

• The synthesis step of the demulsifier is extremely simple. • The demulsifier has a good performance and application potential. • This work provides a new idea for explanation of demulsification mechanism. • The demulsifier can greatly shorten time and reduce temperature of demulsification. A three-branch structure demulsifier (GTE-DDA) for the treatment of water-in-crude oil (W/O) emulsions was synthesized by a one-step method using glycerol triglycidyl ether (GTE) as core and dodecyl amine (DDA) as branched chain. It was characterized by Fourier-transform infrared spectroscopy (FT-IR), nuclear magnetic resonance hydrogen spectra (1H NMR) and thermogravimetric analysis (TGA). Some key parameters such as the concentration of GTE-DDA, settling time, operated temperature and salinity on demulsification efficiency (DE) were systematically explored. The DE reached 87.55% after treating with 400 mg/L of GTE-DDA at 50 °C for 30 min. The demulsifying temperature was significantly lower than those reported in literatures (60-80℃). Especially, a rise in temperature could further improved the DE. In addition, GTE-DDA had an excellent salt tolerance. The possible mechanism was investigated by the interfacial tension (IFT), three-phase contact angle (CA) and microscopic observation. The comparison with commercial demulsifiers showed that GTE-DDA had a great potential for the treatment of crude oil emulsions. [ABSTRACT FROM AUTHOR]

Water-in-oil emulsions are frequently encountered in petroleum extraction. In this paper, CRB-SiO 2 , a cost-efficient and environmentally friendly demulsifier, was synthesized by a two-step method. The chemical structure and surface morphology were analyzed by flourier transform infrared spectroscopy (FT-IR) and scanning electron microscopy (SEM), respectively. The effect of salinity, concentration, temperature and pH value on the demulsification efficiency (DE) was investigated in detail. The DE reached 93.98% with 600 mg/L of CRB-SiO 2 at 70 °C. Also, it had an excellent tolerance of salt, acid and alkali. Moreover, the demulsification mechanism was also studied through three-phase contact angle, interfacial tension and self-assembly of interfacial membrane. CRB-SiO 2 has an amphiphilic structure and lower interfacial tension (IFT) around 37.75 mN/m. Accordingly, it can be easily adsorbed at the water-oil interface, destroying the interface membrane and initiating the separation of oil and water. In summary, CRB-SiO 2 has a potential application in petrochemical industry. [Display omitted] • CRB-SiO 2 was prepared by a two-step method. • CRB-SiO 2 has high demulsification efficiency in water-in-crude oil emulsion. • CRB-SiO 2 is environmentally friendly and highly economical because it uses waste rice bran as raw material. • CRB-SiO 2 has an excellent tolerance of salt, acid and alkali. • The demulsification mechanism has been deeply studied from many aspects. [ABSTRACT FROM AUTHOR]