THE GROUPING COMPOSITION OF ACIDS IN LOW-CALORIC COAL
Acids of different chemical nature are present in the organic matter of the Sergeyevka brown coal deposit. The study of their composition is necessary for technological use of coal, and also represents scientific interest in terms of the presence of the relic carboxilic acids. The paper features the composition of two compound groups: the carboxilic acids of soluble part of coal and the humic acid separated from residual coal matter free from bitumens. It is established that the grouping composition of the carboxilic acids is presented by free compouns and acids bonded in the form of the combined ethers and salts. The separated fractions contain a similar set of of components but they differ in quantitative distribution. They comprise the saturated monocarboxilic acids C10–C28 with high even ratio, dicarboxilic acids from C6 to C18, non-saturated palmitoleic acid, oleic and linoleic acids, aromatic and diterpene acids. It is established that the structure of the humic acids of the study coal corresponds to the general type of the HA structure contained in the hard combustible minerals. They have semi-functional composition and physiological activity which is estimated by the method of 13C NMR spectroscopy.