Evaluation of Scale-up From Analytical to Preparative Supercritical Fluid Chromatography
(English)Manuscript (preprint) (Other academic)
An approach for reliable transfer from analytical to preparative scale in supercritical fluid chromatography was evaluated; here, we accounted for the conditions inside the columns as well to the fact that most analytical instruments are volume-controlled while most preparative scale units are mass-controlled. The latter is a particular problem when performing pilot scale experiments and optimizations prior to scaling up to production scale. This was solved by measuring the mass flow, the pressure and the temperature on the analytical unit by using external sensors. Thereafter, it was revealed with a design of experiments approach that the methanol fraction and the pressure are the two most important parameters to control for preserved retention throughout the scale-up transfer; for preserved selectivity the temperature was most important in this particular system. Using this approach, the resulting chromatograms from the preparative units agreed excellently with those from the analytical unit while2keeping the same column length and particles size. A brief investigation on how the solute elution retention volumes vary with the volumetric flow rate revealed a complex dependency on pressure, density and apparent methanol content. Since the methanol content is a parameter of great importance to control during the scale up, we must be careful when changing operational and column design conditions which generates deviations in pressure, density and methanol content profile between different columns.
IdentifiersURN: urn:nbn:se:kau:diva-37862OAI: oai:DiVA.org:kau-37862DiVA: diva2:851648