STUDY OF THE INTERACTION OF HUMAN ACIDS WITH IONS OF METALS
The interaction of humic acids with copper (II), cobalt (II), and nickel (II) ions at various pH values of the medium was investigated. It is established that the solubility of humic acids in water depends on the pH and increases with an increase in the pH of the medium from 3 to 8. At pH = 8, the solubility of acids reaches a maximum. Reducing the pH below 3 leads to a slight increase in dissolution, which is obviously due to the presence of amino groups in its structure.