Recovery of Phosphates and Metals from Waste Phosphate Sludge by Solvent Extraction.
Powell-HE; Smith-LL; Cochran-AA
NTIS: PB 211 933 :12 pages
A solvent extraction procedure was developed on a laboratory scale for recovering trisodium phosphate, zinc, and iron from waste phosphate sludge as separate products. The sludge was dissolved in hydrochloric acid, and iron was extracted as ferric chloride by isopropyl ether. Zinc was extracted by di-2-ethylhexyl phosphoric acid in kerosine. The efficiencies of the one- and two-stage extractions ranged from 98 to nearly 100 percent. Trisodium phosphate was recovered by crystallization from the raffinate. The value of the two marketable products is considerably more than the costs of the major reagent. The process was developed to permit recycling of values in this waste and to consequently reduce stream pollution from this source.
IH; Report of Investigation;
NTIS Accession No.
NTIS: PB 211 933