Experimental study about the effect of SiO2 nanoparticle in surfactant performance on IFT reduction and wettability alteration

Recently, serious attention to the high potential of nanotechnology in the enhanced oil recovery (EOR) processes have been attracted. In this study, the effects of addition of SiO2 nanoparticle into the aqueous solutions containing octyl phenol ethoxylate (Triton-x100), sodium lauryl sulfate (SLS), and octyl pyridinium chloride ([C8Pyr][Cl]) on the interfacial tension (IFT) reduction, wettability alteration of carbonate rock, and the spreading coefficient were investigated. EDX and FeSEM analysis were taken on the rock that indicate the dolomite nature of the rock sample. The equilibrium IFT and contact angle values of different cases were measured in two series (i.e. with and without SiO2 nanoparticles). It is found that the performance of SiO2 nanoparticle remarkably affected by surfactants type and their combination. SiO2 could not have a positive effect on the IFT reduction and wettability alteration and had an adverse effect on the performance of some surfactants. In more details, SiO2 nanoparticles was able to slightly improve the TiO2 surfactant performance by falling the IFT value from 2.8 to 1.5 mN/m, while it did not have a significant effect on the performance of Pyr surfactant by changing the IFT value from 14 to 13.3 mN/m. The performance order of IFT reduction and wettability alteration was completely different as the lowest IFT and contact angle values were observed for the SLS in the presence of SiO2 (IFT reduction from 0.36 to 0.1 mN/.m) and Tr in the absence of SiO2 (wettability change from 49º to 32.5º), respectively. However, SiO2 nanoparticles have a favorable effect on the spreading coefficient of SLS, Pyr, SLS+Pyr, and SW; among them, the best performance was observed for SLS with spreading coefficient (Sc) value of − 0.06 mN/m.