INVESTIGATION OF CHROMATOGRAPHIC PROPERTIES OF TITANIA. II. INFLUENCE OF CALCINATION TEMPERATURE

Abstract

The characterization of calcined titanias with regard to physical properties as packing materials and crystal forms by X-ray powder diffraction, and the examination of how the ion- and ligand-exchange properties of titania shall be influenced by varying calcination temperature, were demonstrated to elucidate the relationship between the chromatographic behavior and the change of surface state accompanied with varying calcination temperature. The ligand-exchange properties in this experiment were regarded as the formation of chelate rings of 2-hydroxyl aliphatic carboxylic acids. We observed that the physical properties of titania reflected, exactly, the variation in X-ray diffraction patterns with calcination temperature. We found that only calcined titania behaving as cation-exchanger exhibited retention behavior correlated with changes in surface hydroxyl group, and that rutile formed by calcination did not behave as ion- and ligand-exchangers. The absence of these properties would account for losing the surface hydroxyl group and the coordinatively bonded water by calcination.