Analysis of the pulse response in a CSTR for diffusion measurement in bi-porous adsorbent pellets

A theoretical model describing the diffusion and adsorption on bidisperse p orous catalyst during a pulse experiment in a CSTR is presented. The analyt ical solution for dual and single resistance and their long-time solutions are developed. The first moment and the long-time solution of the response curve are used to estimate the parameters and thus avoiding the use of inac curate higher moments. The effect of external surface adsorption is discuss ed. Response curves of propane are measured over HZSM-5 extrudates and prev iously reported curves of propane/butane on 5A pellets are analysed. (C) 20 01 Elsevier Science Ltd. All rights reserved.