| 摘要 |
FIELD: process engineering.SUBSTANCE: invention can be used in chemical industry and production of construction materials. Proposed method comprises processing phosphogypsum by sulfuric solution, filtration, extraction of precipitate of rare-earth metal insoluble compounds and separation of precipitate by filtration. Rare-earth metals are extracted from solution by oxalic acid or its soluble salts at consumption of 250-300 mol % while solution is neutralised to pH=1.0-2.5. Obtained precipitate of oxalates is separated from mother solution, rinsed, dried and calcined.EFFECT: better ecology, higher quality of rare-earth metal concentrate, rules out application of toxic hydrofluoric acid.4 tbl, 6 ex |
