COMPARATIVE-STUDIES OF STRUCTURAL AND SURFACE-PROPERTIES OF POROUS INORGANIC OXIDES USED IN LIQUID-CHROMATOGRAPHY

Structural and surface properties of chromatographic porous silica, al umina, titania and zirconia were studied using thermogravimetry and ni trogen adsorption. The samples studied are mesoporous and exhibit rela tively narrow pore size distributions in the range from 10 to 30 nm, m aking them suitable for chromatographic applications. Low-pressure nit rogen adsorption and thermogravimetry were used to monitor the effects of the thermal treatment on the surface properties of the samples. Th e observed changes in surface properties caused by treatments at diffe rent temperatures were explained in terms of the desorption of physica lly/chemically adsorbed water, which led to exposure of high energy ad sorption sites. (C) 1998 Elsevier Science B.V.