Abstract

The adsorption of surfactants on the reservoir rocks surface is a serious issue in many energy and environment
related areas. Learning from the concept of drug delivery in the nano-medicine field, this work
proposes and validates the concept of using nanoparticles to deliver a mixture of surfactants into a porous
medium. TiO2 nanoparticles (NPs) are used as carriers for a blend of surfactants mixtures including
anionic alkyl aryl sulfonic acid (AAS) and nonionic alcohol ethoxylated (EA) at the optimum salinity and
composition conditions. The transport of NPs through a core sample of crushed sandstone grains and the
adsorption of surfactants are evaluated. By using TiO2 NPs, the adsorption of surfactant molecules can be
significantly reduced, i.e. half of the initial adsorption value. The level of surfactant adsorption reduction
is related to the NPs transport capability through the porous medium. An application study shows that
comparing to surfactant flooding alone, the total oil recovery can be increased by 7.81% of original oil
in place (OOIP) by using nanoparticle bonded surfactants. Such work shows the promise of NP as an effective
surfactant carrier for sandstone reservoirs, which could have many potential applications in
enhanced oil recovery (EOR) and environmental remediation.