A theoretical study on the advantage of core-shell particles with radially-oriented mesopores.
We report on a first-principles numerical study explaining the potential advantage of core-shell particles with strictly radially-oriented mesopores. Comparing the efficiency of these particles with fully porous and core-shell particles with a conventional (i.e., randomly oriented) mesopore network, the present numerical study shows a similar strong reduction in minimal reduced plate height (hmin) as was very recently observed in an experimental study by Wei et al. (respectively a hmin-reduction on the order of about 1 and 0.5 reduced plate height-units). As such, the present work provides a theoretical basis to understand and confirm their experimental findings and quantifies the general advantage of "radial-diffusion-only" particles. Determining the effective longitudinal diffusion (B-term contribution) in a series of dedicated, independent simulations, it was found that this contribution can be described by a very simple, yet fully exact mathematical expression for the case of "radial- diffusion-only" particles. Using this expression, the significant increase in efficiency of these particles can be fully attributed to their much smaller B-term band broadening, while their C-term band broadening (representing the mass transfer resistance) remains unaffected.
Vrije Universiteit Brussel, Pleinlaan 2, 1050 Brussel, Belgium.
Sander
S
Deridder
University of Ferrara, Via Fossato di Mortara 17, 44121 Ferrara, Italy.
Martina
M
Catani
University of Ferrara, Via Fossato di Mortara 17, 44121 Ferrara, Italy.
Alberto
A
Cavazzini
Vrije Universiteit Brussel, Pleinlaan 2, 1050 Brussel, Belgium. Electronic address: gedesmet@vub.ac.be.
Gert
G
Desmet
D000465:Algorithms; D002853:Chromatography, Liquid / Q000295:instrumentation*; D004058:Diffusion; D008962:Models, Theoretical; D010316:Particle Size; D016062:Porosity
B-term band broadening; Computational fluid dynamics; Core-shell particles; General plate height model; Radially oriented pores; Simulations