Adsorption separation efficiency in the cyclic steady state: A continuous countercurrent analogy and an experimental investigation

✍ Scribed by David Gelbin; Gerald Bunke; Hans-Joachim Wolff; Jörg Neinass

• Publisher: Elsevier Science
• Year: 1983
• Tongue: English
• Weight: 632 KB
• Volume: 38
• Category: Article
• ISSN: 0009-2509
• DOI: 10.1016/0009-2509(83)80103-1

✦ Synopsis

For adsorption processes involving concave equilibrium isotherms and finite desorption periods, the choice of cycle time ha5 a decisive intluence on separation efficiency. Using forward-flow desorption, efficiency goes through a maximum at an optimum cycle time; with reverse-flow desorption efficiency increases with decreasing cycle time.

Below, this behavior is explained in terms of a simple graphical solution for the case of a moving-bed countercurrent column, and by comparison with a continuous-flow permeation pmcew An experimental study has been made with the system n-heptane/hydrogenlzeolite NaX at 300°C in a computer-conlrolled benchscale column. Reverse-flow desorption is shown to permit a considerable reduction in the desorption gas volume required to meet efficiency demands.