Inert top layer media

All inert top gradings are developed to replace inert ceramic balls and alumina balls at the top of catalytic reactors, by increasing distribution properties and void fractions to extend cycle length of the units. The larger void fraction and different shapes allow better resistance against particulate deposition (solids such as rust, gum, coke, etc.) or top bed crust formation.

MTE developed the Rest-O inert top gradings product range. With an unique quality control system, MTE can assure and advice the best inert top layer media for your specifications.


  • Improve flow distribution
  • Reduce pressure drop built-up
  • Better resistance against particulate deposition
  • Protection at refinery upsets


  • Naphtha Hydrotreating (NHT)
  • Distillate Hydrocracker (DHC)
  • Hydrodesulfurization (DHS)
  • Hydrodenitrogenation (HDN)
Inert ceramic top layer wheels


  • High void fraction
  • High mechanical strength
  • Good initial distribution
  • high holding capacity for scale and large particulate

Inert ceramic top layer fluted rings


  • More void fraction and bulk density compared to the wheels
  • Designed to trap a higher number of fines compared to the wheels

Inert ceramic and high alumina top layer discs


  • Designed to trap fine particulates from the reactor feed
  • Different mesh sizes to trap different particulates
  • Increase the cycle length in terms of pressure drop built-up compared to other traps
  • In case of sub-5 micron fines, smaller and more dense discs can be provided

Ceramic and high alumina top layer rings


  • Suitable to be used in conjunction with other top layers and catalyst
  • We offer to help in selecting the required type based on void fraction for optimum operation

All above listed inert top grading materials are also supplied in other materials like high purity inert alumina.
For additional information, support or (special) requests, please contact our sales department.

Design recommendations

We are able to make design recommendations for your grading loading diagram

Grading production

We are able to produce grading made from your regenerated catalyst

Grading customization

We customize your grading: any combination of shape and material is possible based on the requirements

Got a mass transfer challenge?

We provide the solution!

Together we achieve optimum performance of your application(s). Please feel free to contact us with any mass transfer related challenge.

+31 10 231 0260


Boezemweg 5

3255 MC Oude-Tonge

The Netherlands