A CSFR system similar to that used by Lassitter et al., was used to conduct the measurements. The experiments were conducted on the same samples of CALF-20 and MOF-303 reported previously. Before the experiments, each sample was regenerated in situ by heating to 100 °C while flowing helium (or nitrogen) across the bed overnight. After regeneration, the sample was allowed to cool to room temperature (25 °C) and then equilibrated with a feed gas containing the desired adsorbate concentration with the balance helium (or helium and nitrogen). After equilibration, the concentration fed to the bed was perturbed in a sinusoidal or square wave manner at a desired frequency.