Gravex® is a complete product line of high-purity, quality-certified cation, anion and mixed bed ion exchange resins.

These custom-blended bead resins are the cleanest bead available, washed and classified, every batch tested and samples filed for future reference.

They are processed to meet nuclear specifications. We offer the most conclusive results available for nuclide removal products. Graver Technologies also supplies bead resin manufactured by Dow, Rohm & Haas and Lanxess (Bayer).

These Gravex Nuclear Grade Ion exchange resins are very high capacity polystyrene, gel type resins. They have been regenerated and processed to provide the highest possible performance in nuclear applications. The Gravex cation is specially processed to minimize leachable sulfonic acids.

Its high capacity and oxidative stability help achieve optimal performance. Gravex mixed beds are the most uniformly blended products available and have the same consistent cation to anion ratio in every package. Our unique blending process creates the less separable GR-3-16 NG stoichiometric mixed bed. A 7Li+ form cation is available as GR-7-16 NG and in the GR-4-7 NG mixed bed.

Proven Technology for the Most Challenging Separations

Powdex® Powdered Resins

Powdex® PAO Series

  • Powdered strongly basic hydroxide form anion exchange resin
  • Highest possible conversion to hydroxide form with very high purity
  • Mixed at point of use with Powdex PCH or PCN to form larger agglomerates
  • Then precoated on Aegis® wound and DualGuard® precoat septa and others in precoat filtration systems known as Powdex filter demineralizers
  • Rapid kinetic performance with excellent hydraulic properties providing simultaneous ion exchange and solids filtration
  • Excellent precoat uniformity essential for proper performance

Typical Applications

  • Nuclear BWR & PWR condensate polishing
  • Nuclear BWR reactor water cleanup
  • Fossil condensate polishing

Click here to download Powdex® Selection Guide.


NANODEX FILTER PAPERS TRACK SYSTEM AND PLANT PERFORMANCE by Monitoring Radionuclide and Corrosion Products

Graver’s patented Nanodex Ion Exchange Filter Papers enable diverse quantitative analyses in the power industry, especially nuclear, to monitor corrosion products, measure activity levels and satisfy fuel warranty requirements.

Nanodex AX 100 anion exchange filter disks contain strongly basic, quaternary ammonium functional sites in the chloride form, which can be converted to the desired ionic form (i.e. hydroxide) as required.

Nanodex CX 200 cation exchange filter disks contain strongly acidic, sulfonic acid functional sites in the hydrogen form. Contact your Graver representative for more information about these innovative filter papers.


  • High performance, specialty hydrophilic paper for a variety of analytical requirements
  • Uniform resin distribution throughout each disk
  • Standard 47mm diameter
  • Highly functionalised, highest ion exchange capacity analytical filter
    disks available
    Filter disks are easily digested by standard analytical methods


  • Excellent hydraulic characteristics
  • Consistent ion exchange capacity and utilization
  • Fit standard bench-top and inline filter holders and housings
  • Single disk used per test
  • Simple to quantify ions removed – X-ray fluorescence or Atomic Absorption


Whether the need is for high purity Gravex® condensate polishing ion exchange resins; the original Aegis® wound, DualGuard® or AFA® pleated filter septa; or the Powdex & Ecodex® families of premium resins, the original and most widely used powdered ion exchange resins, Graver Technologies has the answer for your application.

  • Gravex bead resins for condensate polishing including the lowest residual chloride anion available for treating the most critical operating systems
  • Uniform size Gravex for regenerable deep beds
  • Less separable Gravex for non-regenerable systems
  • Powdex and Ecodex for simultaneous precoat filtration and deionization
  • Aegis precoatable filter septa for Powdex filter demineralizers
  • AFA, the first backwashable pleated filters installed in a condensate pre-filter system
  • DualGuard, combination pleated filter with a precoatable and easily backwashable surface