A Novel Self-Healing Anticorrosive Inhibitor for Pipeline Corrosion Protection in Geothermal Well Systems

The growing demand for energy coupled with the need for environmental sustainability underscores the importance of advancing renewable energy technologies. Among these, geothermal energy stands out as a clean and sustainable resource with substantial potential for heating and power generation. However, the corrosion of materials in geothermal facilities presents a significant operational challenge. This study explores the development of a self-healing anticorrosive coating based on microcapsule technology to address this issue. The proposed coating releases corrosion inhibitors from the microcapsules upon damage, enabling autonomous repair. Microcapsules were fabricated with an oil-soluble imidazoline oleate corrosion inhibitor encapsulated in urea-formaldehyde resin and incorporated into an epoxy resin matrix. The resulting composite coating demonstrated enhanced self-healing properties. Key parameters, including the core-to-wall ratio, healing duration, and microcapsule concentration, were systematically examined for their influence on self-healing efficiency. The performance of the composite was rigorously evaluated through simulated geothermal water corrosion tests under conditions representative of geothermal systems. The results indicate that microcapsules with a core-to-wall ratio of 3:1, using OP-10 as an emulsifier at 0.5 wt % of the core material, exhibited optimal structural integrity and encapsulation efficiency (74.6% core content, 85.7% coating efficiency). Additionally, epoxy resin composites with microcapsule concentrations greater than 20 wt % exhibited effective self-healing of artificially induced damage, demonstrating superior anticorrosive properties crucial for geothermal applications. These findings suggest that the developed self-healing composite holds great potential for mitigating corrosion in geothermal energy systems, contributing to the durability and efficiency of geothermal facilities.