Study on the synthesis and properties of an eco-friendly sugar-based anionic–nonionic surfactant

Abstract

An eco-friendly sugar-based anionic–nonionic surfactant (DAGA-ES) with well-established structure was successfully synthesized and characterized by electrospray ionization-time of flight mass spectrography (ESI-TOFMS), ¹H nuclear magnetic resonance (¹H NMR) and Fourier transform infrared spectrometer (FT-IR). Its adsorption morphology on surface and micelle size in aqueous solution were observed using scanning electron microscope (SEM) and a static laser scattering (SLS) instrument. The surface activities of the solution in the absence or presence of electrolyte were investigated by surface tension measurements. The properties of oil displacement including the ability of reducing oil/water interfacial tension (IFT) and wetting alteration were determined by the rotating drop and contact angle method, respectively. The enhanced oil recovery (EOR) experiment was used to evaluate displacement efficiency. The results indicated that the net-structure could be observed on the surface and the micellar diameter in aqueous solution is 197.2 nm. The fundamental parameters such as critical micelle concentration (CMC), the surface tension at the CMC (γ_CMC), the hydrophile–lipophile balance (HLB) values, maximum surface excess (Γ_max) and minimum surface area (A_min) were obtained via surface tension measurement. In addition, the consequence of the oil displacement property showed that IFT could be reduced to 10⁻² mN m⁻¹ in an electrolyte solution without any surfactant additives. Furthermore, with the DAGA-ES concentration increasing, the hydrophilicity for both of the hydrophilic surface and lipophilic surface was gradually enhanced. Wettability reversal was achieved just on the lipophilic surface. The oil displacement experiment showed that the oil recovery increased by 16.29% using DAGA-ES versus 12.82% using AES.