METHOD OF PROCESSING OF IRON-CONTAINING MONAZITE CONCENTRATES Russian patent published in 2016 - IPC C22B59/00 C22B3/10 C22B1/02 

FIELD: chemistry.

SUBSTANCE: method includes processing of concentrate with diluted hydrochloric acid with obtaining hydrochloric acid solutions FeCl₂ and LnCl₃. Then, decomposition of residue and obtaining of solution, which contains rare-earth metals, are carried out. Before processing with diluted hydrochloric acid monazite concentrate is subjected to reduction at 350-400°C with carbon monoxide (CO). Processing of reduced concentrate is carried out with diluted hydrochloric acid for 15-60 minutes at room temperature. Decomposition of de-ironed concentrate is realised by fluoridation with hydrofluoric acid, or ammonium hydrofluoride, or their mixture, or by sulphatisation of concentrated H₂SO₄, or by processing with concentrated NaOH solution.

EFFECT: realisation of possibility to carry out processing of monazite concentrates and low concentrations of hydrochloric acid at low temperatures for a short time.

4 cl, 1 dwg, 2 tbl, 3 ex