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Accueil du site > Français > Les annonces de séminaires et thèses > Séminaire de Gert DESMET (Vrije Universiteit Brussel, Department of Chemical Engineering)

Séminaire de Gert DESMET (Vrije Universiteit Brussel, Department of Chemical Engineering)

Date  : Mardi 7 novembre 2017, 10 h 30

Titre  : Understanding the Effects of Order and Disorder in Liquid Chromatography.

Lieu  : Salle B. Auvray (Bât. 15, RdC)

Abstract :

Liquid chromatography is a billion dollar business targeting the analysis of the chemical composition of food, the environment, pharmaceuticals, our body, cancer cells,… This is due to the fact that liquid can split a given mixture in a vastly larger number of different fractions than any other physical and chemical separation technique. Whereas for example filtration or extraction can usually only split a mixture in a few fractions, state-of-the-art chromatography columns can easily separate some 10 to 50 components in the span of a few minutes to half an hour. To achieve this high separation resolution, extremely low degrees of axial dispersion are required (corresponding to Bodenstein numbers running in the 10,000s).

This low degree of dispersion is however far from sufficient to meet with the new separation challenges emanating from the area of life sciences, where the need to separate samples containing hundreds and thousands components and requiring Bodenstein numbers running in the millions in order to achieve a satisfactory separation resolution.

To study how the degree of dispersion is linked to the microscopic geometry of packed bed columns, our group follows a combined approach of numerical modeling of both the axial and radial dispersion in a diversity of packing geometries, both ordered and disordered and . The ultimate goal is to find a theory that can describe how dispersion in packed columns changes when a packing gradually changes from a fully random to a completely disordered state. Besides measurements on actual chromatographic columns, we have also developed an experimental approach where we use microfluidic model structures of 2D micro-pillar beds with different packing geometries and using a motorized microscope stage to follow how injected fluorescently labeled molecules migrate and disperse through the chip.