Release:2015, Vol. 1. №2(2)
About the author:Arkadiy A. Kayugin, Cand. Sci. (Chemistry), Associate Professor, Department of Organic and Ecological Chemistry, Tyumen State University
Abstract:The study concerns adsorption of ortho- and para-cresols, catechol, resorcinol, hydroquinone, benzoic, salicylic, p-hydroxybenzoic acids onto natural kaolinite depending on concentration and pH. The sorption experiment was conducted under static conditions at simultaneous presence of phenols or carboxylic acids in the solution at a constant ionic strength, with subsequent determination of the equilibrium concentration of substances by HPLC with a UV detector. We studied the dependence of the level of extraction of substances from the solution on the number and position of functional groups. The position of the hydroxyl groups on the benzol ring has a more pronounced effect on the sorption of organic molecules than their number. Hydroxyl groups showed greater affinity to the kaolinite surface than carboxyl groups. The pH-dependence of acids and phenols sorption is more pronounced at higher initial concentrations of the compounds. The obtained regularities may be extended to the sorption of natural organicsubstances, in particular humic substances onto clays.
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