METHOD OF PRODUCING ULTRAFINE PARTICLES OF HOMOGENEOUS OXIDE CERAMIC COMPOSITIONS CONSISTING OF CORE AND OUTER SHELLS Russian patent published in 2020 - IPC C01B13/14 C04B35/01 C04B35/628 

FIELD: chemistry.

SUBSTANCE: invention relates to the technology of producing ultrafine particles of homogeneous oxide ceramic compositions consisting of a core and outer shells, and can be used in chemical industry, production of ceramics, ceramic articles by additive technologies. Ultrafine particles are obtained by mixing salt solution with oxide particles to apply outer shells on particles from oxide core, by spraying obtained suspension - precursor and thermal treatment of particles. At precursor preparation step, oxide sol, forming nucleus, and solution of metal compounds forming shells from oxides are mixed at ratio of not less than 0.20 in terms of dry components. Oxide sol used is an aqueous nanodispersed sol SiO₂ or Al₂O₃. Solutions of metal compounds which form shells around the core are aluminium chloride AlCl₃ or magnesium chloride MgCl₂. Spraying of precursor is carried out with propane-butane mixture at ratio of precursor and spraying agent of not more than 0.01. Thermal treatment is combined with spraying and is carried out in electrically heated combustion chamber of precursor at temperature not lower than temperature of thermal hydrolysis of solutions of metal compounds.

EFFECT: disclosed method provides higher efficiency, lower multi-staged and labour-consuming method, which enables to obtain particles of ceramic compositions for additive technologies.

1 cl, 4 dwg, 2 ex