Homogeneous metal (no support): pellet
Zirconium, Titanium, Vanadium
Support material, disbursed metal: pellet
Copper, Nickel, Palladium, Platinum
Homogeneous material: pellet
Molecular sieves

Gas Purification Process - Principles of Operation

Catalytic oxidation process
  • Conversion of reducing species
    (H2, CO, CH4 and NMHCs) into CO2 and H2O

  • Recipe: Catalyst + heat + oxygen
    Palladium, Platinum
    300 - 400 C

  • Relationships:
  • 1 H2 + ½ O2 = 1 H2O
    1 CO + ½ O2 = 1 CO2
    1 CH4 + 2 O2 = 1 CO2 + 1 H2O
Physical adsorption
  • Molecular Sieves
  • Can remove CO2 and H2O
    Room temperature operation
    Moderate to low capacity
    Significantly affected by partial pressures
    Significantly affected by temperatures
    Fully reversible with heat and pure gas
Chemical adsorption
  • Catalysts (as adsorbers): Copper, Nickel...

  • Metals can sorb O2, CO, H2
    Support can physisorb H2O and (CO2)
    Room temperature operation
    Relatively low capacity, not significantly affected by partial pressures
    Fully reversible at elevated temperatures
    NiO + H2 + Heat = Ni + H2O
  • Getters: Zirconium, Vanadium...

  •    Can remove N2, CH4, O2, H2O, CO, H2 and CO2
       Heated operation for optimized performance
       Relatively high capacity, not significantly affected by partial pressures
       Surface Adsorption
       Bulk Diffusion
       Irreversible process
Heated Diffusion

Heated Diffusion
© 2022 Rainer Lammertz