title: Effects of thermal heterogeneity in hydrophobic interaction chromatography.
abstract: Manipulating temperature and salt concentration can have a powerful effect on the separation effectiveness in hydrophobic interaction chromatography (HIC). However, use of temperature as an operating variable in large-scale applications may involve undesirable consequences such as radial heterogeneity of the column temperature. In this study non-ideal effects of heat transfer in HIC columns were analyzed. The radial temperature gradients were measured by thermocouples immersed in a bed packed into a preparative column. The column wall was either thermostatted by a water jacket or left under ambient conditions. The influence of ineffective column thermostatting and of heat losses on the radial temperature profiles was demonstrated and predicted by a model of heat dispersion in a packed bed. To analyze possible positive or negative effects of thermal heterogeneity on band propagation, non-isothermal chromatographic elution of a model protein (alpha-chymotrypsinogen A) was recorded under salt gradient conditions as well as at constant salt concentration. To predict temperature and concentration profiles a model of the column dynamics was used. The model accounted for kinetics of mass and heat transfer. A good agreement between experimental and simulated profiles was achieved. It was shown that by proper selection of the process conditions undesirable temperature effects can be avoided or controlled.
authors.affiliation: Chemical and Process Engineering Department, Rzeszow University of Technology, W. Pola Str., 2, 35-959 Rzeszow, Poland.
authors.forename: Renata
authors.initials: R
authors.lastname: Muca
authors.forename: Wojciech
authors.initials: W
authors.lastname: Piatkowski
authors.forename: Dorota
authors.initials: D
authors.lastname: Antos
mesh_terms: D002853:Chromatography, Liquid / Q000295:instrumentation / Q000379:methods*; D002919:Chymotrypsinogen / Q000737:chemistry* / Q000302:isolation & purification; D057927:Hydrophobic and Hydrophilic Interactions; D007700:Kinetics; D011485:Protein Binding; D013696:Temperature
chemical_list: D002919:Chymotrypsinogen