title: Modelling of retention in analytical supercritical fluid chromatography for CO2-Methanol mobile phase.
abstract: Mathematical modelling of the chromatography process requires knowledge of the isotherm model. Therefore a necessary step in calculations is estimation of the isotherm model parameters. In this study the inverse method has been successfully used to estimate the linear isotherm model parameters in supercritical fluid chromatography (SFC). Estimation was based on measured retention times of experimental band profiles. The solute was n-octadecylbenzene. The mobile phase was carbon dioxide-methanol, 95/5% (v/v), and the column was 250mm×4.6mm i.d. packed with 5-micron Luna C18(2) particles. The experiments were done for outlet pressures from 100bar to 150bar at different flow rates and different sets of experimental conditions: (1) column operated under convective air (CA); (2) column operated in still air conditions. Moreover in the latter thermal mode were considered two cases. In the first case the temperature of the oven air was different from the inlet temperature of the mobile phase. In the second case the temperature of the oven air was the same as inlet temperature of the mobile phase. The column efficiency was also analysed.
authors.affiliation: Department of Chemical and Process Engineering, Rzeszow University of Technology, 35-959 Rzeszow, Poland.
authors.forename: Marek
authors.initials: M
authors.lastname: Leśko
authors.forename: Donald P
authors.initials: DP
authors.lastname: Poe
authors.forename: Krzysztof
authors.initials: K
authors.lastname: Kaczmarski
mesh_terms: D002245:Carbon Dioxide / Q000737:chemistry*; D025924:Chromatography, Supercritical Fluid / Q000379:methods*; D000432:Methanol / Q000737:chemistry*; D008962:Models, Theoretical
chemical_list: D002245:Carbon Dioxide; D000432:Methanol
keywords: Column efficiency; Heat balance; Inverse method; Isotherm model; Mass balance; Supercritical fluid chromatography