13X Molecular Sieve specifications
| Property | Unit | Bead Ø1.6–2.5 mm | Bead Ø3.0–5.0 mm | Pellet 1/16" | Pellet 1/8" | Test condition |
|---|---|---|---|---|---|---|
| Static H₂O adsorption | % wt | ≥ 26.5 | ≥ 26.5 | ≥ 26.5 | ≥ 26.5 | RH 75%, 25 °C |
| Static CO₂ adsorption | % wt | ≥ 18.5 | ≥ 18.5 | ≥ 18.0 | ≥ 18.0 | 250 mmHg, 25 °C |
| Bulk density | g/ml | ≥ 0.64 | ≥ 0.64 | ≥ 0.61 | ≥ 0.61 | Tapped |
| Crush strength | N | ≥ 30 | ≥ 85 | ≥ 30 | ≥ 50 | Avg. of 25 beads |
| Loss on attrition | % wt | ≤ 0.10 | ≤ 0.10 | ≤ 0.10 | ≤ 0.20 | — |
| Loss on ignition | % wt | ≤ 1.5 | ≤ 1.5 | ≤ 1.5 | ≤ 1.5 | 550 °C, 1 h |
Where is 13X Molecular Sieve used?
13X molecular sieve is used where water and CO₂ must be removed together or larger molecules such as mercaptans must be adsorbed: air purification, gas sweetening, LPG treatment and PSA oxygen.
Air separation pre-purification
Removes CO₂ and water ahead of the cold box.
Hydrocarbon purification
Dries and de-CO₂s propane, butane and LPG.
13X Molecular Sieve vs other adsorbents: which do you need?
Choose 13X when H₂O and CO₂ must be removed together or larger molecules are present; use 13X APG in ASU pre-purification and lithium LSX for high-output oxygen.
| Grade | Pore | Adsorbs | Typical use |
|---|---|---|---|
| 4A | 4 Å | H₂O, CO₂, H₂S | Natural gas, air, refrigerant drying |
| 5A | 5 Å | n-paraffins, CO, CO₂ | PSA hydrogen, paraffin separation |
| 13X (this product) | ≈ 10 Å | H₂O + CO₂ together, mercaptans | Gas sweetening, purification |
| 13X APG | ≈ 10 Å | CO₂ and H₂O, low dust | Air separation pre-purification |
| Lithium LSX | X-type | N₂ (highest N₂/O₂ selectivity) | PSA / VPSA oxygen |
What is 13X Molecular Sieve?
13X molecular sieve is a synthetic sodium X-type zeolite (NaX) with an open framework and pores of about 10 Å, giving it the highest capacity of the standard grades for water and CO₂.
Type
Sodium X-type zeolite
Adsorbs
H₂O, CO₂, H₂S, mercaptans
Excludes
Very large molecules (> 10 Å)
How does 13X Molecular Sieve work?
The large 10 Å pores admit most small and medium molecules, and the strong field of the sodium cations holds polar and quadrupolar ones such as water and CO₂ much more tightly than hydrocarbons, N₂ or O₂.
- Feed passes through the bed — air, natural gas or liquid hydrocarbons.
- H₂O, CO₂ and sulfur compounds are adsorbed — together, in one layer.
- Purified stream leaves the bed — ready for liquefaction, cryogenic separation or sale.
When should you use 13X Molecular Sieve?
Use 13X when one bed has to remove water and CO₂, or sulfur compounds too large for 4A and 5A.
- Feed carries CO₂ or mercaptans as well as water.
- Higher capacity per kilogram is needed than 4A can give.
- Oxygen is produced by PSA from air.
How do you regenerate 13X Molecular Sieve?
Regenerate 13X thermally with hot, dry purge gas, typically 200–300 °C, or by pressure / vacuum swing in PSA oxygen units.
TSA temperature
200–300 °C
PSA / VPSA
Pressure or vacuum swing
Bed life
3–5 years (TSA)
