METHOD OF EXTRACTING CHROMIUM (VI) FROM SOLUTIONS TO OBTAIN IRON-CHROMIUM PRECIPITATE Russian patent published in 2019 - IPC C02F1/62 C02F1/70 C01G37/00 C01G49/00 C02F101/22 C02F103/16 

FIELD: chemistry.

SUBSTANCE: invention can be used in electroplating in recycling chromium-containing effluents. Method of extracting chromium (VI) from chromium-containing solutions of galvanic production to obtain low-water-bearing iron-chromium-containing precipitate involves adding to chromium-containing solution concentrated sulphuric acid in amount of 6–120 ml/l and crushed steel chips as a reducing agent with subsequent maintenance until decolouration of the solution. Steel shavings with specific surface area of 2.5–2.8 m²/kg is taken in amount of 800–1500 g/l and before loading is activated by successive chemical degreasing and holding in solution of sulphuric acid with concentration of 100–200 g/l or etching solution without acid corrosion inhibitor.

EFFECT: invention increases completeness of extraction of chromium from chromium-containing solutions.

1 cl, 4 dwg, 2 tbl, 5 ex