Hydrochloric Acid Digestion and Solvent Extraction of Western Phosphates.
NTIS: PB 250 652 :21 pages
The Bureau of Mines conducted laboratory tests to evaluate the production of high-purity h3po4 by hcl digestion and solvent extraction. Both batch and bench-scale continuous tests were made. Western phosphate rock concentrates were acidulated with hcl, and the digestion liquors were processed by solvent extraction. Phosphoric acid was extracted with isoamyl alcohol and recovered from the organic extract by contact with an nh4f solution. This solution was fractionally distilled to yield high-purity h3po4. The raffinate from solvent extraction was treated with lime to precipitate caf2, which was subjected to steam pyrolysis to generate hf. This method was successful in recovering 95 pct of the phosphate and 80 pct of the fluoride contained in the concentrates.
IH; Report of Investigation;
NTIS Accession No.
NTIS: PB 250 652