Lignin-Reinforced Thermoset Coatings for Extreme Conditions of Temperature and Pressure

Corrosion of equipment and pipelinesin the oil and gasindustry,particularly under high pressure and high temperature (HPHT) conditions,necessitates high-performance anticorrosive coatings derived fromfossil binder materials and energy-intensive pigments. With the aimof integrating sustainable biomaterials into industrial coating systems,this study investigates the stability of Kraft lignin-reinforced epoxynovolac (LEN) coatings under HPHT. These extreme conditions were simulatedin a non-stirred batch reactor with gas (N₂ and CO₂ mixture), hydrocarbon (aromatic para-xylene), and seawater(SW) phases at 100 bar pressure. Incorporating lignin particles inepoxy novolac coatings inhibited the hydrocarbon softening of thebinder network, preventing the reported underfilm corrosion at HPHT.The findings demonstrated that LEN coatings can withstand HPHT conditionsup to 120 °C. Above this temperature, the presence or absenceof CO2 affected the barrier properties of LEN coatingsin the SW-exposed zone. A life-cycle assessment highlighted the environmentalimpact of LEN coatings for sustainable coating applications. This study investigates the use of lignin,a biomass-derivedbyproduct, to enhance the durability of protective coatings in extremeenvironments, offering potential to reduce fossil material relianceand environmental impact.