Isolation of Fulvic Acids by Extraction with n-Butanol
摘要
The article considers the methods of fulvic acid (FA) extraction from brown coals by the Tyurin–Forsyth method and by liquid-phase extraction with n-butyl alcohol. The data of technical and elemental analysis and IR and 13C NMR spectroscopy of the obtained fulvic acid samples and their fractions are presented. A comparative characterization of the obtained fulvic acids is carried out. It was established that the fulvic acid fractions obtained by the Tyurin–Forsyth method had a higher aromaticity index ( far = 32.79–61.54%) than the fulvic acids obtained by liquid-phase extraction with n-butyl alcohol ( far = 20.64%). Conclusions were made on the possibility and efficiency of using the liquid-phase extraction method with n-butyl alcohol for extracting brown coal fulvic acids.