Rheological Investigation of Water-Based Drilling Fluids Using Synthesized ZnO with TiO2 and Activated Carbon

The primary goal of this study was to improve the rheological properties of water-based drilling mud using a combination of TiO2-coated ZnO nanoparticles and activated carbon (AC) from banana peels. The TiO2/ZnO nanocomposites were prepared using polyvinyl alcohol (PVA) as a binder under magnetic stirring and ultrasonic sonication to ensure uniform coating, followed by washing and controlled thermal treatment. NaOH-assisted chemical activation of banana peel produced activated carbon with better porosity and surface functionality than raw banana peel. The base water-based mud used in this study had different concentrations of both additives mixed in, and rheological parameters such as mud density, plastic viscosity (PV), yield point (YP), and gel strength were measured according to standard API methods. X-ray diffraction (XRD) and scanning electron microscopy (SEM) were used for structural and morphological characterization, which proved the successful coating and uniform dispersion of TiO2 on ZnO nanoparticles. The use of mixed additives resulted in a significant improvement in mud properties, such as viscosity, gel strength, and yield point, proving to be more effective in suspension capacity and overall rheological stability. The use of this hybrid bio-nanocomposite mud system is a very economical and eco-friendly way of enhancing the drilling fluid performance, thus proving to be a supporting factor in conducting drilling operations that are both safe and efficient. Additionally, this study provides a sustainable hybrid TiO2-ZnO and activated carbon additive that results in synergistic improvement of drilling-mud rheology and stability.