Inorganic compounds of sunflower stems

Abstract

This paper presents the results of studying the inorganic components of sunflower stems. The test objects are the extracts obtained at different pH values of the medium and ash samples before and after treatment of stems with water, acid, and alkali. The results show that the nature of the extractant has a negligible effect on the yield of extractive substances from the crushed stems. According to atomic absorption analysis, the main ions in extracts obtained in different media are potassium, calcium, magnesium, and sodium ions. The mass fraction of ash after treatment of stems with solutions at different pH values varies from 0.5 to 5.2%. The lowest ash yield is characterized by a sample of stems after acid extraction. According to energy dispersive X-ray fluorescence spectroscopy, all ash samples contain mainly K, Ca, Mg, and P compounds. The ash components of the core and outer part of the stem were also studied in comparison with the original sample. The ash content of the stem core (9.3%) is higher than that of the outer shell (7.4%). The IR spectroscopy shows that the nature of band splitting in the IR spectra of the ash samples practically does not depend on the stem part and the pretreatment of raw materials at different pH values. Absorption bands characteristic of carbonates and silicates are observed in the IR spectra of the stem ash. According to X-ray diffraction analysis, the studied ash samples are in a crystalline state.