Computer training simulation of monolithic column HPLC

Jetse C. Reijenga1 and Milan Hutta2

1Eindhoven University of Technology, NL2Comenius University Bratislava, SK

ISSS 2005 Pardubice, Czech Republic12-14- September 2005

why? to visualize, illustrate, animate

H. McNair, Basic Liquid Chromatography, http://hplc.chem.shu.edu/HPLC

Computer training simulation of monolithic column HPLC

J.C. Reijenga, MEKC animation (SDS conc change) from http://edu.chem.tue.nl/ce

application of computer simulations

demonstration classroom teaching

practical training in (dry) lab as step towards optimization

original software specs #1

200 - 400 nm

0 - 65 oC 75 samples

J.C. Reijenga, J. Chromatogr. A 903 (2000) 41-48

original software specs #2

50 - 500 mm

0.1 - 25 mm

1 - 250 µm

MeOHACNTHF

J.C. Reijenga, M. Hutta, J. Chromatogr. A 903 (2000) 41-48

5 - 500 mm

1 - 10 mm

1 - 25 µm

MeOHACN

other software extensions #1

• Zorbax C8 • Lichrospher100 RP18 5µm• Lichrospher100 CN 5µm• Spherisorb ODS-2 5µm• Aluspher100 RPSelectB 5µm• TSKgel Super ODS• ChromolithPerformance RP C18e

extensions #2, model refinement

• 2 parameter model• Valid 20 - 50%• Real experiments

• 3 (4) parameter model• Valid 5 - 90%• ChromSword

extensions #3, display options

modeling monoliths #1 pressure drop

Kozeny-Carman relation: ΔP = u L / B0 

with specific permeability: B0 = 3 dp2 / Kc (1 - )2

where the Kozeny "constant" Kc = 180 for spherical and 300 for

monoliths, why?……. a (macro) posority dependence: Kc()

N. Vervoort, P. Gzil, G.V. Baron and G. Desmet, Anal. Chem. 2003, 75, 843-850

column ε (range)Spherical 0.5 (0.4-0.6)Monolithic 0.8 (0.7-0.9)

Dynamic pressure drop display

modeling monoliths #2 plate height

Jennifer Houston Smith, thesis, Virginia Polytechnic Inst. & State Univ. Blacksburg, 2002

H = A + B / u + C * u (omitting the Cs term)

• A = 2 * γ * dp (obstruction factor γ = 0.6)

• B = 2 * kD * Dm (packing factor kD = 0.4)

• C = 1/96 * dp2 / Dm * (11k2 + 6k + 1)/(k + 1)2

(get Dm from Wilke-Chang: solvent, , T and MW effects )

(for convenience: dp = particle or macro pore diameter)

"a 2 m monolithic column behaves like a 4 m conventional"

So for monoliths: dp is replaced with 2 dp (same γ and kD values)

Monolithic column 150 mm, 50% ACN, temperature 65 0°C

Conventional column, 150 mm, 35°C, particle diameter 110 µm

conclusions