SORPTION OF RARE-EARTH ELEMENTS BY ORGANIC MATTER FROM AQUEOUS SOLUTIONS ACCORDING TO EXPERIMENTAL DATA

Abstract

Laboratory model experiments have shown that peat, brown coal and its constituent organomineral components, as well as microscopic fungi isolated from brown coal, are characterized by a high potential for the extraction of all lanthanides from aqueous solutions. The processes of sorption of rare-earth elements by the components of organic matter proceed through the mechanisms of physical sorption, ion-exchange reactions involving carboxyl and hydroxyl groups, and complex formation involving –OH, –CO, and –COOH groups. SEM-EDS analysis revealed REE-containing mineral phases on fungal biomass, which are formed due to interaction with phosphorus- and nitrogen-containing functional groups of cell wall proteins. This indicates the participation of the biotic component in the formation of rare earth mineralization in brown coal deposits.