RU97114573A - METHOD FOR REMOVING TECHNIQUE FROM METAL HAVING RADIOACTIVE CONTAMINATION - Google Patents

Claims (11)

1. The method of removing technetium from a metal having radioactive contamination, characterized in that it includes the following steps
dissolving in an aqueous solution of acid the target metal contaminated with technetium to obtain a working solution containing ions of the above metal and ions of pertechnetate;
the interaction of the aforementioned working solution with a solid base metal having a reduction potential lower than that of technetium and in a form with a high surface area, such contact carries out the reduction of the above pertechnetate ions and the deposition of technetium metal on the surface of the above base metal through a substitution reaction, and thereby a purified solution is produced containing the ions of the above base metal; and
the implementation of the extraction of the above target metal from the above purified solution.  2. The method for removing technetium from a metal having radioactive contamination according to claim 1, characterized in that the above target metal is nickel.  3. The method for removing technetium from a metal having radioactive contamination according to claim 2, characterized in that the above base metal is selected from the group consisting of nickel, zinc, tin, lead, copper, mercury and mixtures thereof.  4. The method of removing technetium from a metal having radioactive contamination according to claim 3, characterized in that the above base metal is nickel.  5. The method of removing technetium from a metal having radioactive contamination according to claim 2, characterized in that the above acid solution is a solution of sulfuric acid.  6. The method of removing technetium from a metal having radioactive contamination according to claim 1, characterized in that the above base metal is in powder form. 7. The method of removing technetium from a metal having radioactive contamination according to claim 1, characterized in that it includes further steps
providing an electric cleaning bath having a cathode and anode compartments separated by a semipermeable membrane;
providing a mass of the above solid base metal;
providing a cathode in the above cathode compartment;
the use of the above target metal contaminated with technetium as an anode in the above anode compartment;
the use of the above aqueous acid solution as anolyte;
continuous supply of the above anolyte from the above anode compartment through the above mass of the base metal in the above cathode compartment and
applying an electric current to the above anode and cathode immersed in the above aqueous acid solution to dissolve the above anode and deposit the above target metal from the above purified solution on the above cathode.  8. The method of removing technetium from a metal having radioactive contamination according to claim 7, characterized in that a portion of the above anolyte leaving the above mass of the base metal is returned to the above anode compartment.  9. The method of removing technetium from a metal having a radioactive contamination according to claim 8, characterized in that the liquid level in the above cathode compartment is maintained at a higher level than in the above anode compartment, so that the difference in hydrostatic pressure through the above membrane is ensured, and the above the difference directs the aforementioned aqueous acid solution from the aforementioned cathode compartment to the aforementioned anode compartment through the above membrane. 10. The method of removing technetium from a metal having radioactive contamination according to claim 1, characterized in that it includes further steps
providing an electric cleaning bath having a cathode and anode compartments separated by a cationic, ion-selective membrane;
providing a mass of the above solid base metal;
providing a cathode in the above cathode compartment;
the use of the above target metal contaminated with technetium as an anode in the above anode compartment;
the use of the above aqueous acid solution as anolyte;
continuous supply of the anolyte from the above anode compartment through the above mass of the base metal to the above cathode compartment; and
applying electric current to the above anode and cathode immersed in the above aqueous acid solution to dissolve the above anode and deposit the above target metal from the above purified solution on the above cathode.  11. The method of removing technetium from a metal having radioactive contamination according to claim 10, characterized in that a portion of the above anolyte passing through the above mass of base metal is returned to the above anode compartment.