Molecular Dynamics Simulation of Nanoparticle‐Driven Oil Detachment in Nanochannels

Abstract Nanoparticles exhibit significant potential in modulating oil‐water interfacial tension, altering rock wettability, and optimizing fluid flow for enhanced oil recovery. This study employs MD simulations to investigate the effects of surface‐modified nanoparticles (pure‐NP, alkyl‐NP, carboxylate‐NP) on interfacial tension, layer thickness, and displacement energy. Results reveal that alkyl‐NP reduces interfacial tension most effectively (32.57 mN·m⁻¹), followed by carboxylate‐NP (38.64 mN·m⁻¹) and pure‐NP (45.02 mN·m⁻¹). Alkyl‐NP also demonstrates the greatest reduction in oil‐particle interaction energy (−500 kcal/mol), while Pure‐NP and Carboxylate‐NP show weaker displacement capacity. Notably, nanoparticle addition significantly increases the interfacial layer thickness ( t oil : 9.5 ∼ 17.4 Å, t water : 7.9 ∼ 12.5 Å, t total : 13.4 ∼ 22.5 Å) compared to the pure system ( t oil = 4.8 Å, t water = 3.8 Å, t total = 6.5 Å). These findings suggest that nanoparticle systems enhance oil recovery by lowering interfacial tension, thickening interfacial layers, and improving crude oil stripping and migration. Alkyl‐NP emerges as the most promising modifier due to its superior interface control and energy reduction.