(337bf) Towards Sustainable Energy and Materials: Carbon Capture, Utilization and Storage

Research Interests: CO₂ capture, Direct air capture (DAC), Adsorption, Separation, CO₂ mineralization, Particle technology, Fluidization

My Ph.D. research focused on carbon mineralization using silicate minerals and alkaline industrial wastes for CO₂ utilization and storage. The fate and reactivity of silicate materials are important for carbon sequestration, where CO₂ is captured and stored as a thermodynamically stable solid carbonate phase. Thus, understanding the structures and chemistry of different silicate phases has become an important research aim. In my work, ²⁹Si MAS NMR and dissolution kinetic study were integrated to identify underlying mechanisms of elemental extraction and reactivity of silicate materials. Additionally, I designed a unique internal grinding reactor system to enhance diffusion-limited elemental extraction behaviors.

To expand my knowledge and skill set, I researched developing hybrid carbon capture materials by encapsulating highly viscous CO₂ capture solvents. This approach aimed to enhance the kinetics of direct air capture and point-source CO₂ capture. The solvents have been encapsulated inside a CO₂-permeable polymer matrix as a microemulsion phase and the capture kinetic was significantly improved by increasing the gas-solvent interfacial area. I aimed to optimize the encapsulation method for CO₂ capture solvents and foster a fundamental understanding of mass transfer and chemical reaction in gas (CO₂) – liquid (solvents) – solid (polymer shell) systems.

My postdoctoral research focused on the synthesis and characterization of amine-impregnated porous materials, including Metal-Organic Frameworks (MOFs) and alumina, for direct air capture applications. Through extensive equilibrium and kinetic CO₂ capture experiments, I have evaluated their CO₂ adsorption performance and studied the competitive adsorption of CO₂ and moisture under cold temperature conditions (unconventional, rarely studied, extreme yet still practical conditions) to cover an array of global deployment locations for DAC technologies. This study highlights the importance of understanding the interaction between amine and solid support materials for the development of efficient direct air capture (DAC) technologies. The differences in CO₂ sorption behavior between the two supported amine materials, tetraethylenepentamine (TEPA) supported on γ-Al₂O₃ and MIL-101(Cr), under varying temperatures (-20 °C to 25 °C) and humidity (0 to 70% RH) conditions suggest that the choice of support material can significantly impact the CO₂ capture mechanisms of impregnated amines. Therefore, proper selection of solid support materials for amine impregnation is essential for achieving optimized DAC performance under varied deployment conditions, such as cold (e.g. -20 °C) or ambient temperature (e.g. 25 °C) operations. This research has significantly enhanced my expertise in adsorption and separation processes, as well as MOF synthesis and characterization.