Revolutionizing shale drilling with potassium chloride-based natural deep eutectic solvent as an additive

Abstract Shale instability is a significant problem, accounting for approximately 70% of wellbore challenges during drilling operations. To address this issue, shale inhibitors are commonly added to mud stabilize the encountered formations. Ionic liquids and deep eutectic solvents have been recognized as effective due their environmental friendliness effectiveness. However, despite advantages, these solutions still lack full sustainability, leading researchers explore more natural alternatives like Natural Deep Eutectic Solvents (NADES). This study focuses on synthesis application NADES composed Potassium Chloride (KCl) glycerine, aiming enhance profile efficacy inhibitors. The was prepared with 1:8 molar ratio at temperature 60 °C. Characterization analyses, including Fourier Transform Infrared Thermogravimetric Analysis, confirmed formation bonds between –(OH) Cl − demonstrated NADES's thermal stability up 200 Incorporating 3% into water-based mud, following API 13B-1 standards, resulted in improvements rheology. Specifically, addition reduced filtrate volume by 14.2% cake thickness 19.2%. Furthermore, exhibited remarkable inhibition clay swelling 69.23% recovery rate 58%. When compared KCl 1-ethyl-3-methylimidazolium chloride (EMIM-Cl), NADES-based outperformed both terms efficacy. These findings were further supported additional d-spacing measurements (XRD), Zeta Potential, Surface tension, Field Emission Scanning Electron Microscopy. Additionally, rheological behavior aligned Yield Power Law 25 °C 100 study's contribute advancement greener practices highlight applicability KCl-based potential fluid additive.