METHOD OF SEPARATION OF PALLADIUM FROM NITRATE SOLUTIONS (VERSIONS) Russian patent published in 2002 - IPC

FIELD: separation of palladium on flow- through cathode made from carbon fiber material from aqueous solutions, liquid radioactive waste inclusive. SUBSTANCE: process of separation and cleaning of palladium (Pd) from admixtures, radioactive fission products includes stages of electrochemical deposition of palladium on cathode, washing cathode sediment under voltage and dissolving sediment in strong nitrous acid. Addition of carbamide at concentration of from 0.05 to 0.5 M or nitrate hydroxylamine at concentration of from 0.05 to 0.3 M into starting carbamide solution makes it possible to extract more than 99.99% of palladium (residual content of Pd is lesser than 0.02 mg/l) from solutions at acidity of 0.2 to 4 M of HNO₃, including solutions of complex salt composition, for example, liquid waste of high level of activity after reprocessing of nuclear fuel. EFFECT: increased coefficient of cleaning palladium from fission products and corrosion whose magnitude ranges within 10³-10⁴ for many admixtures contained in liquid waste of high level of activity. 10 cl, 1 dwg, 7 tbl, 24 ex