Acidic and basic properties of the surface of gas-chromatographic sorbents with grafted metal chelate layers

The acidic and basic properties of the surface of gas-chromatographic sorbents based on silica gels with grafted layers of nickel acetylacetonate and nickel-malonic and acetoacetic esters were studied by pH measurements and the Hammett indicators adsorption method. The acidic and basic state of the surface was shown to depend on the ligand of the modifying addition, the structure of the complex, and the structural and sorption properties of the silica gels used.