Mass transfer performance of centrifugal adsorption technology

Centrifugal adsorption technology (CAT) provides a new way of countercurren tly contacting micrometer range adsorbent particles and liquid feed. As a r esult of the fast mass transfer kinetics and countercurrent contact, CAT ca n lead to very compact adsorption equipment with high throughputs and very good separation efficiencies. A model for predicting the performance of CAT is described. The model calculations are based on the steady-state continu ity equations and include mass transfer resistance in both phases as well a s longitudinal dispersion effects in both phases. Data for the degree of ba ckmixing have been taken from earlier work on CAT, The model predictions ar e compared with experimental data for Ca2+/Na+ ion exchange on Dowex 50 WX8 cation-exchange resin in a pilot scale CAT rotor. The experimentally obser ved separation efficiencies range from 90% for a separation factor equal to one, to 99% and beyond for higher separation factors. The model is shown t o give accurate predictions of the performance of CAT. Model calculations d emonstrate that the performance of CAT is limited by the degree of backmixi ng in the adsorbent phase mainly.