Comparison of isomer separation on carbon-clad microporous zirconia and on conventional reversed-phase high-performance liquid chromatography supports

A carbon-clad zirconia-based support is used for the separation of a variety of structural isomers. The separation of these isomers on the carbon-clad zirconia surface is compared to that on a conventional reversed-phase column of higher efficiency. The mobile phases were individually optimized for each isomer separation on both columns. The relative retention of the solutes of interest on carbon and ODS columns are also compared. In general the carbon support has much greater selectivity for the separation of both nonpolar and polar isomers and is considerably more retentive than the conventional reversed-phase support. The retention of the carbon-clad zirconia support is especially high for solutes with polar functional groups attached to an aromatic ring (i.e. nitrotoluene, alkyl aryl ketones, nitroxylenes). Despite the lower chromatographic efficiency of the carbon support, it proved to have better resolving power and provided faster separations than did the conventional column.