(444a) Adsorption Properties of Research-Grade Test Materials for Carbon Dioxide Capture

Direct air capture (DAC) of carbon dioxide by solid sorbents requires the materials to adsorb CO₂ at ambient concentration of ≈ 400 μmol/mol. Reliable materials property data are needed to characterize, model, and evaluate materials to advance material development. An adsorption isotherm, which determines gas uptake as a function of equilibrium pressure, is a key metric for screening the performance of solid sorbents. Currently, no low-pressure CO₂ adsorption reference standards (materials and data) exist from NIST or other organizations for CO₂ at sorption ranges relevant to DAC. The FACT lab at NIST is developing a Research-Grade Test Material (RGTM) for ultralow CO₂ sorption measurements to enable instrument validation, interlaboratory comparison of data, and ultimately accelerate the commercialization of materials for DAC.

Progress on an interlaboratory study looking at CO₂/13X at 25 ºC organized with the Versailles Project on Advanced Materials and Standards (VAMAS), Technical Working Area 39 will be presented. Adsorption properties of second RGTM independently developed through the DAC program at NIST to be utilized for a wider range of measurement techniques will also be presented.