METHOD FOR PROCESSING ZIRCON CONCENTRATE Russian patent published in 2022 - IPC C22B34/14 C22B1/02 C01G25/00 C01B33/00 

FIELD: metallurgy.

SUBSTANCE: invention relates to the metallurgy of rare metals, and in particular to methods for processing zircon concentrate, and can be used to obtain baddeleyite concentrate - a raw material for the production of zirconium-containing products: ceramic zirconium dioxide and metallic zirconium and its alloys, as well as silicon dioxide in the form of a commercial product. A pre-activated zircon concentrate is used, which is mixed with a 10-40% solution of ammonium hydrofluoride at a mass ratio of the concentrate to a solution of ammonium hydrofluoride as 1: (5-20) at a temperature of 25°C to 90°C for 1 - 4 h, catching while ammonia with water to obtain an aqueous solution of ammonia. The solid precipitate filtered from the resulting pulp is dried at a temperature of 60-80°C for 2-6 hours, and then it is calcined at 600-900°C for 1-4 hours, obtaining a baddeleyite concentrate. The off-gases are collected with water and combined with an ammonium fluoride solution after subsequent filtration of the silica slurry. The filtrate is treated with aqueous ammonia solution. The resulting suspension of hydrated silica is filtered, and the precipitate is calcined at a temperature of 500-800°C for 2-6 hours, obtaining silicon dioxide in the form of a product. At the same time, the exhaust gases are trapped with water to obtain ammonium hydrofluoride, which is combined with an ammonium fluoride solution after filtering a suspension of hydrated silicon dioxide and with a solution obtained after trapping gases during drying and roasting of the pulp precipitate. The combined solutions of ammonium fluorides are evaporated at a temperature of 130-170°C, obtaining crystalline ammonium hydrodifluoride for fluorination of a new portion of the original concentrate.

EFFECT: method ensures the processing of zircon concentrate with the production of marketable products - silicon dioxide and baddeleyite concentrate in a closed circuit.

1 cl, 3 ex