Frequency Response Method for Measuring Mass Transfer Rates in Adsorbents via Pressure Perturbation

A new apparatus for the measurement of equilibria and dynamics for gas-phase adsorption systems is utilized to examine the adsorption of carbon dioxide on BPL activated carbon. The apparatus has a flow-through configuration. For dynamics, with constant inlet flow, pressure within the adsorbent-containing section is varied sinusoidally, and the time-dependent outlet flow rate is measured to determine an amplitude ratio and phase lag. Studies are made of temperature effects and particle size effects. Results are compared with several mathematical models. Frequency response data show that the BPL system follows surface (or micropore) diffusion kinetics. The rate of adsorption for the activated carbon is found to be only weakly dependent on the bulk particle size.