Experimental Investigation on Amphiphilic Modified α-Zirconium Phosphate (α-ZrP) Nanomaterials Combined with Surfactants for Enhanced Oil Recovery

Amphiphilic α-zirconium phosphate (α-ZrP) nanosheets were fabricated via a straightforward three-step approach: first, highly crystalline α-ZrP was synthesized by refluxing; next, the bulk α-ZrP was exfoliated into single- or few-layer nanosheets; finally, these exfoliated nanosheets were converted into Janus amphiphilic materials through a partial hydrophobic modification with octadecyltrichlorosilane. A range of characterization techniques was used to verify the morphological and chemical structural properties of the amphiphilic nanosheets. The Janus α-ZrP nanosheets were then combined with a surfactant and evaluated in low-permeability sandstone cores at three different concentrations. The mechanisms underlying enhanced oil recovery (EOR) using the α-ZrP-surfactant composite were analyzed, including the formation of Pickering emulsions and the increased viscosity of the displacing phase. Both emulsion formation and viscosity enhancement of the flooding fluid contribute to improved micro-displacement efficiency. Overall, the findings suggest that amphiphilic modified α-ZrP nanosheets combined with surfactant hold potential for EOR applications in low-permeability reservoirs.