Stabilization of oil/water emulsions using soybean lecithin as a biobased surfactant for enhanced oil recovery

Enhanced oil recovery (EOR) relies on the use of surfactant to flood the wellbore and thus extract the oil from the rocks. However, current surfactants used for EOR are non-biodegradable and are made from toxic chemicals. Here, we report the potential of soybean lecithin as a biobased surfactant for enhancing oil recovery by stabilizing oil-in-water (O/W) emulsions. Our findings show that pH has a significant impact on stability, with lower pH levels leading to improved stability. Salinity affects stability, but soybean lecithin shows minimal sensitivity to salt concentration. Surfactant loading also plays a crucial role, with higher concentrations causing instability. The optimized operating parameters for soybean lecithin are determined to be at pH = 4, salinity = 84,171.08 ppm, and surfactant loading = 4.48 wt.%. Comparative evaluation reveals that soybean lecithin performs competitively, outperforming certain commercial surfactants in terms of emulsion stability in oil phase. The solubilization ratio of oil (SR_o) values are lecithin = 3.2219, CAPB = 0.7028, CTAC = 11.1044, NP10EO = 11.1570, and SLES = 11.7067. Utilizing soybean lecithin as a biobased surfactant in enhanced oil recovery offers a sustainable and environmentally friendly alternative with potential economic advantages. Further research can focus on optimizing formulation and exploring synergies with other additives.