Surface functionalized Fe₃O₄‐polyacrylamide dispersion for improved oil recovery at harsh conditions

Abstract

With the growing demand for energy supply and the natural decline of oil reservoirs, the development of new enhanced oil recovery (EOR) techniques become more and more critical. Polymer flooding EOR is one of the most successful chemical EOR methods but suffers many drawbacks at high temperatures and high salinity (HT‐HS) conditions. Superparamagnetic nanoparticles (NPs) have been recently investigated for subsurface applications, including in EOR, due to their unique physicochemical properties. Their applicability under harsh reservoir conditions, however, is yet to be examined. In this work, a novel approach is developed to synthesize superparamagnetic Fe3O4 (NPs) with unique surface functionalization (SMag‐NPs) and to form stable polyacrylamide (PAM) dispersions (SMag‐NPs‐PAM). Both stability and core flooding experiment results demonstrate the promising future of the new dispersion. The SMag‐NPs‐PAM dispersion is not only stable at HT‐HS conditions, but also show excellent EOR capability at HT‐HS by recovering, 61.72% of the initial oil quantity, which is significantly higher than those from conventinal NPs‐PAM disperison and pure PAM fluid. These findings show the promising application potential of SMag‐NPs‐PAM for improving oil recovery in challenging HT‐HS reservoir conditions.