Abstract
Due to its high solubility and low molecular weight, fulvic acid is a very active participant in natural chemical processes. Due to its smaller molecule size than humic acid, it can act both inside and outside the cell. The work presents the method of isolation and purification of fulvic acid obtained from oxidized brown coal and the analysis of its physical and chemical properties by the methods of IR, NMR spectroscopy, and the amount of carboxyl and hydroxyl groups studied. Conducted work on calculation of equilibrium constant (pK) and concentration (C). Stages of purification: adsorption, ion purification and dialysis, where adsorbents obtained from brown ("Shoptykol") and hard ("Shubarkol") coal and coconut activated carbon were used as adsorbents.