Introduction
Molecular Sieve type 5A is an alkali alumino silicate; it is the calcium form of the Type A crystal structure. Type 5A has an effective pore opening of  5 angstroms (0.5 nm). It will adsorb molecules with a kinetic diameter of less than 5 Angstrom and exclude those larger.
It is especially suitable for PSA adsorber applications where it may be used for the separation of normal- and iso- paraffins (C4 to C6 species), in PSA hydrogen purification and in oxygen concentrators.

 

Typical Chemical Formula
0.7 CaO . 0.3 Na2O . Al2O3 . 2 SiO2 . 4.5H2O
 SiO2 : Al2O3 ≈ 

 Application
 The strong ionic forces of the divalent calcium ion makes it an excellent adsorbent to remove water, CO2, H2S from sour natural gas streams, while minimising COS formation. Light mercaptans are also adsorbed.
 It is also used for the separation of normal- and iso paraffins.
 Production of high purity N2, O2, H2 and inert gases from mixed gas streams.