Modelling methods to aid the design and optimisation of batch stirred-tank and packed-bed column adsorption and chromatography units

• Published in: Journal of Chromatography A 1989-12, Vol.484, p.187-210
• Main Authors: Cowan, G.H., Gosling, I.S., Sweetenham, W.P.
• Format: Article
• Language: English
• Subjects: Analytical chemistry; Chemistry; Chromatographic methods and physical methods associated with chromatography; Exact sciences and technology
• ISSN: 0021-9673
• DOI: 10.1016/S0021-9673(01)88968-8

In this paper, work is described which has led to the development of a suite of computer programs for the prediction of adsorption and chromatographic processes to aid the design and optimisation of batch stirred-tank and packed-bed column units. Brief descriptions are given of the mathematical models incorporated within the codes, and the complementary small-scale experiments to provide the necessary physical parameter information on adsorption isotherms and mass transfer kinetics. The models are formulated for single- and multi-component adsorption and for packed-column separation dealing with both frontal analysis and elution chromatography. Two types of predictive method are outlined. The first is based on simple kinetic type rate expressions for mass transfer, the second is a more complex model taking into account liquid film and pore diffusion resistances to mass transfer. For adsorption the models imply a favourable Langmuir type isotherm but they may be adapted for use with linear and irreversible isotherms. Some details of the mathematics involved in the models and the methods of solution of the resulting equations are presented. In specific cases simplifying assumptions allow analytical solutions to be obtained, whereas in other instances numerical solutions derived by using the Harwell FACSIMILE code are required. Typical results are given from small-scale and pilot-scale experiments to provide data to validate the codes. These experiments involved studies of the adsorption, washing and elution of single- and multi-component amino acids using Duolite A-162 resin spheres as adsorbent covering a range of conditions. Comparisons are given between code simulations and experimental data, and applications of the codes are discussed.