Аннотация
Introduction. The use of liquid organomineral fertilizers (LOMF) based on chelates of microelements and humates leads not only to an increase in yield and product quality, but also to a decrease in economic costs. LOMF s have a complex effect on plants, activate various physiological processes, increase the plant defense mechanism to various stresses and phytopathogens, improve the structure and properties of the soil. The aim of the work is to study the patterns of the influence of sodium humate concentrations on the process of obtaining humate-, nitrogen- and molybdenum-containing LOMFs. Methods. The methods of chemical analysis, an atomic emission spectrometer with inductively coupled plasma, infrared spectroscopy and thermogravimetric analysis were used. Results and discussion. Based on chemical and physicochemical analyses, the effect of sodium humate concentrations on the composition and properties of the synthesized products was determined. The results demonstrated that increasing sodium humate concentrations from 0.1% to 1.0% led to a rise in the yield of humic acids (HAdaf) from 33.73% to 38.60%, nitrogen content from 4.21% to 5.27%, and molybdenum content from 0.22% to 0.30%, the amount of COOH - from 1.28 to 1.80 mg-eq/g and OHphen.groups –from 0.34 to 0.70 mg-eq/g. IR spectral analysis revealed that the interaction of sodium humate with ammonium heptamolybdate results in the formation of a complex compounds. The IR spectra of the LOMF samples exhibited distinct and well-defined absorption peaks at specific wavelengths, indicating an enrichment with carboxyl, phenolic, and carbonyl functional groups. Conclusion. Physicochemical investigations of the synthesized LOMFs confirmed that the interaction of sodium humate with ammonium heptamolybdate leads to the formation of organomineral chelate complexes incorporating molybdenum ions. The formation of these complex compounds, alongside increased concentrations of HAdaf, nitrogen, molybdenum, COOH, and OHphen groups, enhances the biological activity and agrochemical efficacy of the fertilizers.