Ryosuke Okuno

University of Texas at Austin

Alternative Carbon Carrier Technology using Formate Species

Formate species, such as sodium and potassium formate, offer a promising pathway for alternative carbon-carrier technology (ACT) when synthesized from captured CO₂. These compounds are highly soluble in brine, inexpensive, and already widely applied in oil-field operations. Remarkably, one barrel of brine can stably hold the equivalent of 70 kg of CO₂ as formate (HCOO⁻) at standard temperature and pressure, eliminating the need for energy-intensive CO₂ compression. Unlike conventional sequestration strategies that depend on structural and capillary trapping, formate-based ACT enables carbon transport and storage through a miscible water-displacement process while allowing operators to tune brine density for in-situ buoyancy control.

This presentation will first briefly highlight three main research directions—ketone EOR, aqueous nanobubble dispersion, and ACT—before focusing on the latest ACT developments of the Energi Simulation Research Program at the University of Texas at Austin. Current work explores ACT applications in CO₂-enhanced oil recovery, as well as its integration into CO₂ mineralization pathways, positioning formate-based carbon carriers as a versatile and scalable tool in next-generation carbon management.