Preparation and enhanced oil recovery evaluation of amphiphilic boron nitride nanosheets

Abstract

To investigate the potential of amphiphilic nanomaterials in enhancing oil recovery, a novel BN-NH₂ nanosheets were prepared and evaluated. The proposed preparation method for BN-NH₂ nanosheets involved activating BN (boron nitride) surface by sodium hydroxide and subsequently modifying BN using APTES ((3-aminopropyl)triethoxysilane). The successful synthesis of BN-NH₂ nanosheets with a size of 280 nm was confirmed using FT-IR, TGA, SEM, and particle size analysis. The BN-NH₂ nanofluid (1000 mg/L) exhibited excellent stability, maintaining minimal particle size changes after 5 days of standing. At 60 °C, the BN-NH₂ nanofluid (1000 mg/L) maintained an interfacial tension of 10.1 mN/m, highlighting its ability to reduce interfacial tension. At 60 °C, the BN-NH₂ nanofluid (1000 mg/L) achieved an emulsification index of 0.28 after 240 h, demonstrating its excellent emulsification performance. The BN-NH₂ nanofluid (1000 mg/L) effectively altered reservoir wettability, reducing the contact angle from 108.8° to 46.8°. Displacement experiments revealed that BN-NH₂ nanofluid flooding could enhance oil recovery by 16.2 % compared to water flooding. The mechanism of enhanced oil recovery by BN-NH₂ nanofluid was analyzed via microscopic displacement experiments.