(156b) Advanced Structured Material for Direct Air Capture

Mustapha Soukri, Paban Sitaula, Lindsey Chatterton, and Daniel O’Nolan

Research Triangle Institute, 3040 E Cornwallis Rd, Durham, North Carolina, 27709, USA

ABSTRACT:

As fossil fuels remain a major source of energy throughout the world, developing efficient negative emission technologies, such as direct air capture (DAC), which remove carbon dioxide (CO₂) from the air, becomes critical for mitigating climate change.

DAC has been intensively studied in recent years, and a variety of adsorbent materials have been developed to directly capture CO₂ from the air. Among them, amine-based materials are attractive adsorbents for DAC and are widely studied due to their promising performance under humid conditions, lower amine volatilization rates compared to amine solvents, and the strong affinity of amine groups for CO₂. While the amine-containing solid adsorbents are tolerant to moisture in the air, it is generally known that physisorbents are not effective adsorbents for CO₂ capture in the presence of moisture due to competitive adsorption between CO₂ and H₂O, which yields high sorbent regeneration costs.

We have developed an amine-based sorbent for DAC via a reductive amination, cross-linking reaction of polyamine and polyaldehyde compounds. The sorbent adsorbed CO₂ from air up to 5.0 wt.% at 25°C, 75% relative humidity, over 100 cycles. The CO₂ adsorption capacities from simulated air were determined using an advanced gravimetric sorption analyzer and a packed-bed reactor (PBR) respectively. We have then integrated this sorbent to a novel contactor that is optimized for wind-driven operation. Creating an amine sorbent film for DAC on a structured substrate such as a Stainless-Steel plate surface has been developed.

We will present the development results of the sorbent performance under simulated DAC conditions. We will also highlight the effects of common contaminates in air as well as the sorbent kinetics. Furthermore, we will present the outcome of the coating effort of this material on the surface of Stainless-Steel plate including the choice of the binder resins, drying techniques, solvents for coating formulation, viscosity of the coating formulation, adhesion promoters, and surface pretreatments which all play an important role in creating a uniform and strongly bound film to the substrate.