Drilling fluids are essential in oil exploration, balancing technical performance and environmental safety. In line with Sustainable Development Goal 12 (responsible consumption and production), this study formulates an eco-friendly fluid using babassu ester (Orbignya oleifera) as the base oil. A 2 3 factorial design assessed the effects of oil-water ratio, emulsifier concentration, and salinity at 30°C, 60°C, and 90°C. All formulations exhibited pseudoplastic behavior described by the Herschel-Bulkley model. Salinity was the most influential factor, significantly enhancing yield limit, consistency index, and apparent viscosity. Unexpected viscosity increases at 90°C suggest possible thermal degradation, warranting further investigation. While yield stress modeling achieved strong statistical fit, lower R 2 values for thixotropy and viscosity suggest nonlinear behavior better represented by quadratic models. These findings support the use of babassu ester as a sustainable alternative in drilling fluid systems, with potential for environmentally responsible application under varied operational conditions.
Silva et al. (Sun,) studied this question.