Product RAXORB35
RAXORB35 is an inorganic sorbent, based on nickel ferrocyanide (29%) and zirconium dioxide (33%), characterized by thermal, chemical and radiation resistance.

RAXORB35 is particularly selective towards Cesium radionuclides (exchange capacity towards a 0.1% solution of CsCl of about 0.5 mol/Kg) also in presence of highly mineralized solutions because of its stability in alkali environment (up to pH=12).

RAXORB35 is produced in spherical granules sizing 0.4-1mm of density of about 1.07 Kg/dm3, with high mechanical strength thus featuring excellent kinetic characteristics and long life time.

RAXORB35 is suitable for the deactivation of radioactive waters of different salinity and particularly for the sorption of Cesium from process waters in nuclear power plants (i.e. regeneration solutions for the demineralization units, evaporator stillage residues, radioactive liquid wastes, effluent process waters, etc.).

Product Test Cases
  • Deactivation of Process Water at B401, K503 and B504 Nuclear Power Plants
    • Initial activity of 137Cs: 2·10-9 Ci/l;
    • Water flow: 50,000 Vol @ 30 Vol/h;
    • Final activity of 137Cs: 1·10-11 Ci/l.

  • Deactivation of Secondary Condensate of Evaporators at B401 NPP
    • Total activity of the initial condensate of 134,137Cs: 3.4·10-8 Ci/l;
    • Flow rate: 60,000 Vol;
    • Final activity of condensate of 134,137Cs: 4·10-10 Ci/l;
    • Specific activity of the sorbent (filter charge) for 134,137Cs: 9.8·10-4 Ci/l.

Note: during operations the filter charge requires periodic washouts to mechanically clean the cumulated impurities because of the low transparency of the condensate.

  • Decontamination of Stillage Residues at U618 NPP
    • Composition of the initial solution:
      • Total salt content: 180 g/l,
      • Boron compound concentration (BO3): 31.5 g/l
      • pH=10.2
    • Initial activity of Cs: 3.0·10-5 Ci/l;
    • Decontamination factor:
      • For the first 500 Vol: avg. 7,700 (5,000-10,000),
      • At 720 Vol: 350;

Note: Stillage residues are characterized by an alkaline reaction and by the presence of a considerable amount of salts of boron.

RDN's Comparative Test on Stillage Residues

RDN, an independent organization made a comparative test under dynamic condition

s (at a flow rate of 2.5 Vol/h) between RAXORB35 and three other sorbents (See table/chart) on stillage residues initially characterized by:

  • pH=11.4;
  • Total salt content: 484 g/l;
  • Content of H3BO3: 70.8 g/l;
  • Chemical absorption of oxygen: 7.4 g/l;
  • Activity of the initial stillage:
    • 134Cs: 1.13·108 Bq/l,
    • 137Cs: 6.5·106 Bq/l,
    • 60Co: 2.7·105 Bq/l [Note: the stillage residues were pre-oxidized with KMnO4 in order to reduce the specific activity of 60Co in the testing solution to 2·103 Bq/l].