Akintola, S.A.Ehwarieme, F.Amaechi, I.2026-04-3020242457-1024ui_art_akintola_advancing_2024.Current Journal of Applied Science and Technology 43 (12), pp. 44-61https://repository.ui.edu.ng/handle/123456789/13880Drilling fluid is a key element in the drilling process because it lifts cuttings to the surface, maintains a stable wellbore, and generates sufficient hydrostatic pressure to prevent the influx of formation fluids into the wellbore. While oil-based drilling fluids offer advantages like wellbore stability, lubrication, and temperature resistance, disposing of oil-contaminated cuttings, particularly those using diesel, harms the environment. This study explores the use of coconut oil and shear butter oil, a renewable and biodegradable resource, as the base for oil-based drilling fluids. Two samples of coconut oil and shea butter oil-based mud samples were formulated and tested in the laboratory against the conventional crude oil-based mud. Laboratory tests compared each sample of coconut oil and shea butter oil-based mud against conventional diesel-based mud. Tests included FTIR characterization of additives, and evaluation of gel strengths, yield point, viscosity, and emulsion stability at 120°F and 300°F. Filtration loss and mud thickness were also measured. Results indicate that coconut oil and shea butter oil-based drilling fluids offer promising rheological properties and environmental benefits. Coconut oil-based sample (VCO I) exhibited superior viscosity and emulsion stability, though it produced a thicker mud cake, indicating a need for optimization. These alternatives present a viable solution to reduce the environmental impact of drilling operations. Further research and field trials are recommended for practical application.enRheologydrilling fluidoil-based mudtemperatureenvironmentally friendlyAdvancing sustainability of drilling fluid: coconut and shea butter oils as alternative to dieselArticle