Metal storage capacity evaluation of humic and himatomelanic acids hydroxymethyl derivatives obtained from brown coal

Humic substances represent the most extensive and reactive class of natural compounds. A more nature-saving way is to obtain humus substances from solid combustible minerals and waste from their processing. The ability of these compounds to form stable complexes with heavy metals, which increases with their directed chemical modification, has been experimentally confirmed. The effectiveness of the phenol-formaldehyde condensation method for the modification of initial humus substances has been confirmed. The interaction of humic and himatomelanic acids with formaldehyde leads to an increase in sorption activity in comparison with the initial humic acids with respect to heavy metals. This aspect has been studied and confirmed in model experiments with copper ions. Key words: humic substances, brown coal, humic and himatomelanic acids, directed chemical modification, hydroxymethyl (methyl) derivatives, heavy metals, copper ions, complex formation.