Siberian Federal University

Using the method of scanning electron microscopy in combination with energy dispersive X‑ray spectroscopy (SEM-EDS), a systematic study of the shell compositions of individual globules of different morphology of a narrow fraction of cenospheres from fly ash from the pulverized combustion of Ekibastuz coal was carried out. Significant differences in the composition of particles with a ring and network structure have been established, concerning both the main macrocomponents SiO2 and Al2O3 and impurity oxides FeO, CaO, MgO, TiO2. The shell of both types of globules is heterogeneous in composition and it contains of the fragments with an increased content of silicon, aluminum, calcium, magnesium, and titanium. The structure-forming mineral precursors of the ring structure cenospheres are NH4- and K‑illite, and the network structure cenospheres are kaolinite