Molecular Sieves 5A 1/16

Molecular Sieves 5A, the calcium form of the crystal structure, is analkali metal alumino-silicate. 5A will adsorb molecules with criticaldiameters up to 5 angstroms.

Molecular Sieves 5A is the molecular sieve adsorbent which made possiblethe separation of normal paraffins from banched-chain and cyclic hydrocarbonsthrough a selective adsorption process. It is now used commerciallyin large-scale n-paraffin separation processes.All molecules which can be-adsorbed-on-Molecular Sieves 3A and 4A canbe adsorbed on Molecular Sieves 5A.

[Typical Properties]Nominal Pore Diameter: 5 AngstromsPellet length: approx. 2 ~ 6 mmParticle Diameter: approx. 1/16 inchesEquilibrium H2O Capacity: approx. 20 ~ 25 % (g H₂O/100 gactivated adsorbent at 17.5 mm Hg, 25 degrees C)Molecules Adsorbed: Molecules with an effective diameter < 5 angstromsMolecules Excluded: Molecules with an effective diameter > 5 angstroms,e.g. iso compounds-and-all 4 carbon rings.

[Regeneration]Molecular Sieves 5A can be regenerated for re-use by purging or evacuatingat elevated temperatures. However, repeated exposure to temperaturesover 590 degrees C should be avoided. In practice, water is removed byheating the material at 200 to 315 degrees C. The degree of regeneration(water removal) is dependent on the temperature and humidity of the purgegas.In liquid phase operation, all liquid should be drained from the MolecularSieves before regeneration. Reverse flow is advantageous in all regenerations.