METHOD OF PRODUCING HOLLOW MICROSPHERES OF ALUMINIUM OXIDE Russian patent published in 2021 - IPC C01F7/02 C01F7/30 B22F9/30 B01J20/08 B01J32/00 B82B3/00 B82Y40/00 

FIELD: chemistry.

SUBSTANCE: invention relates to production of inorganic fillers from hollow nanoscale aluminium oxide used as a base of sorbents, carriers of catalysts, fillers for heat-resistant and heat-insulating coatings. Method of making hollow microspheres of aluminium oxide involves hydrothermal treatment of aqueous solution of aluminium nitrate and fructose, washing of product of hydrothermal treatment in form of carbon core with shell from aluminium oxide with distilled water, drying and annealing in air to obtain hollow microspheres of aluminium oxide, wherein concentration of aqueous solution of aluminium nitrate is 0.001–0.050 mol/l, and fructose - 0.01–0.50 mol/l, the process is carried out in two steps: first at temperature of 100–125 °C and pressure of 0.5–1.0 MPa for 1–4 hours, and then at 175–200 °C and pressure of 3–5 MPa for 5-25 hours. Hydrothermal treatment product can be annealed at temperature of 600–800 °C.

EFFECT: invention enables to obtain hollow microspheres of aluminium oxide with average size of not more than 100 nm with simultaneous simplification of the process of their production.

1 cl, 2 ex