SOME ADSORPTION PHENOMENA OF NITROANILINES ON ALKALINE EARTH COMPOUNDS

Abstract

The spectral behavior of o- and p-nitroanaline adsorbed on various alkaline earth compounds has been studied by reflectance spectroscopy. Regular bathochromic shifts in the diffuse reflectance spectra have been observed for the absorption maxima in the visible region in order of increasing size of the adsorbent cation. Progressive removal of coadsorbed moisture which competes for active adsorbent sites resulted in an enhancement of the bathochromic shifts. The intensity of the absorption maxima as measured by peak heights was found to be dependent upon the size of both cations and anions of the adsorbents. Interpretation of observed phenomena was advanced in terms of electronic polarization theory and varying surface area of the adsorbents.