CaX Molecular Sieve specifications
| Property | Unit | Value | Test condition |
|---|---|---|---|
| Diameter | mesh | 6×8 | — |
| N₂ adsorption | [ml/g] | ≥ 18.0 | 760 mmHg, 25 °C |
| Crush strength | N / bead | ≥ 25 | Avg. of 25 beads |
| Bulk density | g/ml | ≥ 0.60 | Tapped |
| Loss on ignition | % wt | ≤ 1.5 | 575 °C, 1 h |
| Loss on attrition | % wt | ≤ 0.3 | — |
Where is CaX Molecular Sieve used?
CaX molecular sieve is used in cryogenic air separation pre-purification units to remove N₂O, and as the nitrogen adsorbent in VPSA oxygen plants.
Air separation pre-purification
Removes N₂O and trace hydrocarbons ahead of the cold box.
CaX Molecular Sieve vs other adsorbents: which do you need?
Choose CaX when N₂O removal matters in the pre-purification unit; 13X APG is the standard for H₂O and CO₂, and lithium LSX gives the highest N₂/O₂ selectivity for oxygen.
| Adsorbent | Main strength | Typical use |
|---|---|---|
| CaX (this product) | N₂O and N₂ adsorption | PPU layer, VPSA oxygen |
| 13X APG | H₂O and CO₂ removal | PPU main layer |
| Lithium LSX | Highest N₂/O₂ selectivity | PSA / VPSA oxygen |
What is CaX Molecular Sieve?
CaX molecular sieve is an X-type zeolite exchanged with calcium ions, whose strong electrostatic field makes it adsorb N₂O and N₂ more strongly than sodium 13X.
Type
Calcium-exchanged X zeolite
Adsorbs
N₂O, N₂, trace hydrocarbons
Form
6×8 mesh beads
How does CaX Molecular Sieve work?
Divalent Ca²⁺ cations create strong adsorption sites that hold quadrupolar and polar molecules such as N₂ and N₂O more strongly than O₂.
- Air flows through the bed — in a PPU layer or a VPSA adsorber.
- N₂O (PPU) or N₂ (VPSA) is adsorbed — purified air or oxygen passes on.
- Bed is regenerated — by heated purge gas in a PPU or by vacuum in VPSA.
When should you use CaX Molecular Sieve?
Use it when your air separation plant must control N₂O slip, or when you run a VPSA oxygen unit designed for a calcium X adsorbent.
- PPU design calls for a dedicated N₂O-removal layer.
- VPSA oxygen plant specified with CaX.
- Replacement of an existing CaX charge.
How do you regenerate CaX Molecular Sieve?
In a PPU it is regenerated thermally with dry heated purge gas; in VPSA oxygen units it is regenerated by vacuum every cycle.
PPU
Heated dry purge gas, 150–200 °C
VPSA
Vacuum desorption
Service life
[Years]
