Fluoropolymer-coated SiO2 nanoparticle-based nanofluids for oil recovery

The wettability of the reservoir is critical in the extraction of oil and gas resources as well as the flowback of working fluid. The movement of the liquid phase in the reservoir with water-wetting and oil-wetting has a high adhesion resistance, which is not conducive to the exploitation. To address the issues, we have developed a series of nanomaterials. Fluompolymer nanofluids with core-shell structure were prepared from fluorinated monomers and nano-silica. The average size distribution is at the range of 260-370 nm, and the median size is about 160-190 nm. After the treatment of 0.10 wt% fluoropolymer nanofluids, the contact angle between core and water/n-hexadecane changed from 28 degrees/0 degrees to 147 degrees/130 degrees, the core surface free energy decreased from 66.6 mN/m to 0.92 mN/m, the water imbibition of the core decreased from 1.38 g to 0.18 g, and the injection balance pressure of displacement reduced from 7.0 MPa to 2.0 MPa. Wettability has been altered, and the core's wettability has changed from amphiphilicity to amphiphobicity. It has the potential to reduce the adhesion resistance between the fluid and the reservoir. Energy consumption is lowered while displacement and recovery efficiency are improved. Furthermore, the putative mechanism was examined using experiment findings and molecular modeling.