The article is devoted to the problems of aluminate solutions sorption purification from harmful organic impurities in the production of alumina from the Bayer experiment. The study of sorption of basic classes of organic impurities isolated from industrial aluminate solutions showed that magnesium and calcium hydrocarboaluminates have a high selectivity in relation to the most harmful classes of organic substances for the process. The results of the sorption process kinetics and thermodynamics studies are given, optimal technological parameters of sorption purification and conditions for the synthesis of active sorbents from alkaline aluminate solutions and activated magnesium and calcium raw materials are determined.