The increasing interest in employing nanofluids within the oil and gas sector has spurred significant research efforts. This study focuses on the formulation of two bio-nanofluids, comprising aluminum oxide nanoparticles suspended in isopropanol alcohol. Environmentally friendly dispersion stabilizers, namely egg and soy protein, were individually incorporated into the nanofluid formulations. The chemical composition and particle size distribution of the resulting nanofluids were rigorously characterized using X-ray diffraction (XRD) and dynamic light scattering (DLS) analyses, respectively.

Interfacial tension measurements between the bio-nanofluids and crude oil were conducted across a range of salinities, specifically 1, 3, and 5 wt.% NaCl solutions. Analysis of the oil recovery data revealed a notable improvement in performance with the soy protein-based nanofluid (SAO), exhibiting approximately a 36% enhancement in oil recovery at a concentration of 0.3 wt.% soy protein and 0.5 wt.% aluminum oxide nanoparticles and isopropanol. Similarly, the egg protein-based nanofluid (EAO) demonstrated a significant improvement of 33% in oil recovery at a concentration of 0.7 wt.% egg protein and 0.7 wt.% aluminum oxide nanoparticles and isopropanol. This discrepancy in performance was attributed to SAO's superior ability to reduce interfacial tension with crude oil, achieving a lower value of 0.03 mN/m compared to 0.04 mN/m for EAO at 3% NaCl.