Using Three NIST Reference Zeolite Materials to Study the Effect of Pore Metrics on the Measurement of High-Pressure CO2 adsorption Isotherm

Many commercial and industrial applications, such as gas separation, catalysis, environmental remediation, and gas capture and storage relies on solid adsorbents with suitable pore metrics. Ongoing efforts to cost-efficiently curtail carbon dioxide (CO₂) emissions from stationary sources (such fossil fuel-fired power plants and natural gas purification stations) have increased interest in developing CO₂ adsorbents that require little energy to recover the adsorbed CO₂. Although new and improved CO₂ adsorbents continue to emerge, the pace of innovation is hindered by the lack of reliable criteria to optimize experimental parameters and the lack of robust methods to characterize the CO₂ adsorption behavior of materials, especially at high-pressures. In an effort to establish such criteria, we have selected three NIST reference zeolite materials: RM-8850 (zeolite Y), RM-8851 (zeolite A) and RM-8852 (ZSM-5 zeolite) to measure high-pressure CO₂ adsorption isotherms at 20 °C and up to 45 bar. Based on their distinct pore characteristics, these reference materials were used to test methods to optimize experimental parameters in adsorption isotherm measurements. The preliminary results and details of the optimized measurement criteria will be presented.