| Autor: |
Sam Wouters, Tom Hauffman, Marjo C. Mittelmeijer-Hazeleger, Gadi Rothenberg, Gert Desmet, Gino V. Baron, Sebastiaan Eeltink |
| Přispěvatelé: |
HIMS Other Research (FNWI), Sustainable Chemistry, HCSC+ (HIMS, FNWI), Chemical Engineering and Industrial Chemistry, Faculty of Engineering, Materials and Chemistry, Electrochemical and Surface Engineering, Industrial Microbiology, Centre for Molecular Separation Science & Technology, Department of Bio-engineering Sciences, Vriendenkring VUB, Chemical Engineering and Separation Science |
| Jazyk: |
angličtina |
| Rok vydání: |
2016 |
| Předmět: |
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| Zdroj: |
Journal of Separation Science, 39(23), 4492-4501. Wiley-VCH Verlag |
| ISSN: |
1615-9306 |
| Popis: |
Poly(styrene-co-divinylbenzene) monolithic stationary phases with two different domain sizes were synthesized by a thermally initiated free-radical copolymerization in capillary columns. The morphology was investigated at the meso- and macroscopic level using complementary physical characterization techniques aiming at better understanding the effect of column structure on separation performance. Varying the porogenic solvent ratio yielded materials with a mode pore size of 200 nm and 1.5 μm, respectively. Subsequently, nano-liquid chromatography experiments were performed on 200 μm id × 200 mm columns using unretained markers, linking structure inhomogeneity to eddy dispersion. Although small-domain-size monoliths feature a relatively narrow macropore-size distribution, their homogeneity is compromised by the presence of a small number of large macropores, which induces a significant eddy-dispersion contribution to band broadening. The small-domain size monolith also has a relatively steep mass-transfer term, compared to a monolith containing larger globules and macropores. Structural inhomogeneity was also studied at the mesoscopic level using gas-adsorption techniques combined with the non-local-density-function-theory. This model allows to accurately determine the mesopore properties in the dry state. The styrene-based monolith with small domain size has a distinctive trimodal mesopore distribution with pores of 5, 15, and 25 nm, whereas the monolith with larger feature sizes only contains mesopores around 5 nm in size. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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