Cross-linked chitosan encapsulated hollow mesoporous silica nanoparticle: A dual-functional smart nanocapsule design for targeted corrosion inhibition and controlled emulsification

Research on stimuli-responsive micro-nanocontainers has gained attention for targeted corrosion inhibition and controlled emulsification-demulsification in oil recovery. However, existing nanocontainers face issues like irreversible drug release and limited functionality. This study presents a multi-functional nanocontainer design with reversible drug release and emulsification-demulsification capabilities. The fabricated nanomaterial BTA@HMSNs-CS, i.e., hollow mesoporous silica nanocontainers (HMSNs) loaded with 1H-Benzotriazole (BTA) and coated with crosslinked chitosan (CS), can transport BTA to corrosive areas in oil wells for targeted corrosion inhibition, and emulsify oil droplets in deep underground oil reservoirs for enhanced recovery. The imine bonds within the cross-linked CS layer demonstrate sensitivity to pH variations, dynamically adjusting the CS polymerization degree. This mechanism controls the BTA release from HMSNs-CS, achieving long-term corrosion inhibition of metal. When reaching deep underground oil reservoirs, the HMSNs-CS nanocontainers exhibit stable adsorption at the oil-water interface, preventing oil droplet aggregation and reducing the oil-water interfacial tension. This results in the formation of stable Pickering emulsions, facilitating demulsification in acid and emulsification in neutral/alkaline environments, and ultimately ensuring improved oil recovery efficiency. In this study, the developed nanomaterial exhibits dual-functions of corrosion inhibition and emulsification, offering an integrated strategy for metal protection and oil recovery in oil and gas operation.