Typical chemical formula: Na2O/Al2O3/2SiO2/4.5 H2O
SiO2: Al2O3 ≈2
Regeneration:
Type 4A can be regenerated by either heating in case of thermal swing processes or by lowering pressure in case of pressure swing processes
Remove moisture from 4A molecular sieve
Required temperature: 200 to 230°C
Properly regenerated molecular sieve can give moisture dew points below -100°C
Outlet concentrations on pressure swing process will depend on gas present and on conditions of process
Size:
Zeolites are available in beads: 1 to 2, 2 to 3mm (10 x 18 mesh), 1.7 to 2.5mm (8 x 12 mesh), 3-5mm (4 x 8 mesh), as powder and in pellet 1.6/3.2 inches
Applications:
Drying and removing of CO2 from natural gas, LPG, air, inert and atmospheric gases
Removal of hydrocarbons, ammonia and methanol from gas streams (ammonia syn gas treating)
Special types are used in air break units of buses, trucks and locomotives
Packed in small bags, it may be used simply as packaging desiccant
Attention: to avoid damp and pre-adsorption of organic before running or must to be reactivated
