Fixed Feed Temperature Programmed Modulation (FFTPM) a quantitative method to obtain thermophysical physisorption parameters: Application to CWA adsorbents

Assessing the interaction between an adsorbate and a surface is essential for optimal engineering and design of adsorbents. For low-vapor-pressure adsorbates, which also exhibit relatively weak adsorption behavior (physisorption), both the sample and the system (manifolding, reactor, etc.) demonstrate similar affinities for the probe molecule. To minimize errors, researchers often use large sample masses, which are not often convenient to obtain, particularly for new lab-generated materials. To circumvent this issue, we demonstrate an approach where we fix the thermodynamic state of the system, and then thermally perturb a small sample under fixed feed conditions, thus eliminating the impact of the system response. By varying the thermal modulation rate, various regimes for analyzing adsorption, desorption, and reactions are possible, which enables the extraction of thermophyiscal parameters. In this paper, we first validate the fixed feed temperature-programmed modulation (FFTPM) method against a common ...