Group D molecules

Specific adsorbents with positive surface charges. Acidic hydroxyl groups (hydroxylated acid oxides such as silica), aprotic acid centers, or small radius cations (zeolites) on the surface. Adsorbents of this type will interact with molecules which have locally concentrated electron densities, that is. Group B and Group D molecules. 

Group D Molecules. These molecules have adjacent bonds, one with a positive charge and one with electron density. Molecules with -OH and =NH functional groups, for example, H2O, ROH, and T and 2° amines, constitute this group. Group D molecules may interact specifically with... 

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