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.).

• 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].