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Recovery and Separation of Molybdenum and Rhenium from a Process Solution.
Fischer DD; Bauer DJ; Lindstrom RE
NTIS: PB 247 791 :12 pages
Recovery and separation of molybdenum and rhenium from a process solution was accomplished by a technique developed by the federal Bureau of Mines involving a combined solvent extraction and activated carbon adsorption procedure. The processing sequence required treatment of the solution with so2 to reduce the chlorate ion and adjust the ph prior to solvent extraction of molybdenum and rhenium with a Tertiary amine. Molybdenum and rhenium were stripped from the organic phase with an nh4oh solution, and the strip solution was then passed through activated carbon to preferentially adsorb the rhenium. After washing entrained molybdenum from the column with a brine solution, rhenium was eluted with an meoh-h2o mixture. The activated carbon was regenerated with water. Molybdenum was recovered as (nh4)6mo7o24 by evaporating the column effluent. Rhenium in the column eluate was reextracted with a Tertiary amine, stripped from the organic phase with dilute nh4oh, and recovered as nh4reo4 by evaporating the strip solution. The final (nh4)reo4 product contained <80 ppm impurities. Sodium sulfate was crystallized from the first solvent-extraction raffinate by lowering the solution temperature to 0 deg c. Precious metals contained in the original process solution were adsorbed onto the activated carbon.
IH; Report of Investigation;
NTIS Accession No.
NTIS: PB 247 791
Page last reviewed: November 26, 2021
Content source: National Institute for Occupational Safety and Health Education and Information Division