Modeling shock layers in ion-exchange displacement chromatography

✍ Scribed by Venkatesh Natarajan; Steven M. Cramer

• Publisher: American Institute of Chemical Engineers
• Year: 1999
• Tongue: English
• Weight: 139 KB
• Volume: 45
• Category: Article
• ISSN: 0001-1541
• DOI: 10.1002/aic.690450104

✦ Synopsis

In ideal displacement chromatography systems with infinite mass-transfer kinetics , ®arious solutes are separated by sharp discontinuities. In real systems, howe®er, the shocks are eroded into shock layers because of the finite rates of mass transfer. The thickness of these shock layers, which can reduce the yields achie®able in these systems, depend on the flow rate, particle diameter and the '' difficulty'' of these separations. The steric mass action formalism of ion-exchange chromatography was used in concert with a solid film linear dri®ing force model to describe the effects of flow rate, particle diameter, and the degree of difficulty of the separation on ion-exchange displacement systems. Simple pulse techniques are employed to estimate the thermodynamic and mass-transfer parameters. The simulations are then compared to experimental results o®er a range of conditions. The results demonstrate that this relati®ely simple modeling approach can be employed to describe the beha®ior of these nonideal displacement systems.