Zirconia carbon-clad

Gray, M., Dennis, G.R., Wormell, P., Shalliker, R.A., Slonecker, P. (2002). Two-dimensional reversed phase separations isomeric separations incorporating C18 and carbon clad zirconia stationary phases. J. Chromatogr. A 975, 285-297. 

Zirconia particles have been promoted recently as support replacing silica with the proposed advantage of better chemical, thermal, and mechanical stability. Such zirconia-supported chiral phases have been prepared by Park and coworkers [77] through coating, for example, of 0-9-[3-(triethoxysilyl)propylcarbamoyl]quinine onto 5 p.m zirconia particles (30-nm pore diameter) or carbon-cladded zirconia particles as support [78]. In comparative tests with corresponding silica materials. 

Carr and others have described the preparation and properties of polybutadiene (PBD) and polyethyleneimine (PEI), as well as aromatic polymer-coated and carbon-clad zirconia-based RP phases. The preparation of PBD-coated zirconia and the chromatographic evaluation of these phases have been described extensively by Carr, McNeff, and others [39 1]. From these studies, the authors conclude that at least for neutral analytes PBD zirconia-coated phases behave quite similar with respect to retention and efficiency compared to silica-based RP phases [42]. For polar and ionic analytes, however, substantial differences with respect to retention, selectivity, and efficiency have been reported [43]. 

Weber, T.P. Jackson, P.T. Carr, P.W. Chromatographic evaluation of porous-carbon-clad zirconia microplates. Anal. Chem. 1995, 67, 3042-3050. 

Figure 1 Illustration of the isomeric separation of oligostyrene containing four configurational repeating with a sec-butyl end group on (A) a Cl8 column (250mm x 4.6 mm, Pd 5 pm) and (B) a carbon clad zirconia column (100mm x 4.6mm, Pd 3pm). Both separations were in a mobile phase of 100% acetonitrile at 30°C.

Figure 2 Chromatograms of pyrene illustrating the band tailing that is observed on a carbon clad zirconia reversed-phase column in comparison to a CIS reversed-phase column.

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