(256e) Functionalized Iron Oxide (Fe3O4) Nanoparticles As a New Type of Recyclable Hydrate Dispersant

The agglomeration of gas hydrates in flowlines may disrupt the normal operation and even block them, causing enormous financial loss. The current solution is to inject low-dosage hydrate inhibitors or surfactant-like anti-agglomerant. The concerns about using such chemicals are mainly about the cost, toxicity, and environmental impact. More recently, nanoparticles have been investigated to be a potential candidate for dispersing small hydrate particles and allowing them to flow in a slurry form. In this work, we coated 20 nm iron oxide particles with different hydrophobicity and studied their impact on hydrate dispersion. The response of iron oxide nanoparticles to the magnetic field was also utilized for recycling. Both on a microscopic scale with in-situ observations at ambient conditions and on a macroscopic scale with high-pressure rock-flow cell experiments, we explored the performance of nanoparticles with different extent of surface modifications. With proper surface modifications, the iron oxide nanoparticles prevented small hydrate particles from agglomeration. Furthermore, we investigated efficient particle recycling strategies with a magnetic field. The nanoparticles were fully detached from the oil-water interface by adding a tiny amount of surfactant (0.5% to the water phase). After drying, they can be readily reused, reducing the cost and minimizing environmental concerns.