Abstract <p>New sorbents based on Silipor 200 have been synthesized. The adsorption properties of their surface in relation to the following classes of organic compounds were studied: aliphatic alcohols, aldehydes, ketones, and esters. Chelate-type complex compounds were used as modifying additives to obtain noncovalently modified adsorbents: cobalt acetyl acetonate, benzoyl acetonate, ethyl acetoacetate, and diethyl malonate. The retention of organic substances was studied by gas chromatography, and the thermodynamic parameters of adsorption and Henry constants were calculated. The influence of the functional groups of the chelate on the adsorption heats, the adsorption entropy change, and the contributions of cobalt chelates on the SiO₂ surface to the retention of adsorbates were determined.</p>