METHOD FOR PRODUCING POWDER OF COMPOSITE BISMUTH, IRON AND TUNGSTEN OXIDE WITH PYROCHLORE PHASE STRUCTURE USING MICROREACTOR WITH INTENSIVELY SWIRLING FLOWS Russian patent published in 2023 - IPC B22F9/24 C01G29/00 C01G49/06 C01G41/02 B82Y40/00 

FIELD: chemistry.

SUBSTANCE: invention relates to the production of nanosized and/or submicron powders of a complex oxide with a pyrochlore structure of composition (Bi₂O₃)_0.42(Fe₂O₃)_0.28(WO₃), which can be used to create photoelectric energy converters, for photocatalytic cleaning and disinfection of air and water. The solution of bismuth and iron nitrates is mixed with a solution of sodium tungstate to form a suspension, the suspension is mixed with an alkali solution to form an amorphous precursor suspension having pH=2-2.4, the amorphous precursor suspension is hydrothermally treated, the resulting powder is washed and dried. The initial solutions are mixed in a flow mixing reactor, a microreactor with intensively swirling flows. Hydrothermal treatment of an amorphous precursor suspension is carried out in a flow-through multichannel autoclave at a temperature of 190-210°C for at least 2 hours. Washing of the obtained powder and its separation from the mother liquor is carried out in an electroflotation machine, and drying of the obtained powder is carried out by a combination of suspension spraying and a fluidized bed at a temperature of 80-90°C. The supply of the drying agent under the fluidized bed grate is carried out in a pulsed mode.

EFFECT: obtaining a powder of homogeneous composition and structure and high productivity.

1 cl, 6 dwg, 3 tbl, 2 ex