Molecular Sieve type 3A is an alkali metal alumino-silicate; it is the potassium form of the type A crystal structure. Type 3A has an effective pore opening of about 3 angstroms (0.3nm). This is large enough to allow in moisture, but excludes molecules such as unsaturated hydrocarbons which can potentially form polymers; and this maximizes lifetime when dehydrating such molecules
Typical Chemical Formula
0.4K2O 0.6Na2O Al2O3 2.OSiO2 4.5H2O
SiO2 : Al2O3 ≈2
Technical Parameter
Item |
Unit |
Technical data |
|
|
|
Shape |
|
Pellet |
|
Sphere |
|
Diameter |
mm |
1.5-1.7 |
3.0-3.3 |
1.7-2.5 |
3.0-5.0 |
Size ratio up to grade |
% |
≥98 |
≥98 |
≥98 |
≥98 |
Bulk density |
g/ml |
≥0.65 |
≥0.65 |
≥0.70 |
≥0.70 |
Wear ratio |
% |
≤0.20 |
≤0.25 |
≤0.10 |
≤0.10 |
Crushing strength |
N |
≥45/cm |
≥60/cm |
≥30/p |
≥70/p |
Static water adsorption |
% |
≥20 |
≥20 |
≥20 |
≥20 |
Ethylene adsorption |
% |
≤3.0 |
≤3.0 |
≤3.0 |
≤3.0 |
Water content, as shipped |
% |
≤1.5 |
≤1.5 |
≤1.5 |
≤1.5 |
Typical Application
1.Drying of unsaturated hydrocarbons (e.g. ethylene, propylene, butadien)
2.Cracked Gas Drying
3.Drying of natural gas, if COS minimization is essential, or a minimum co-adsorption of hydrocarbons is required.
4.Drying of highly polar compounds, such as methanol and ethanol
5.Drying of liquid alcohol
6. Static, (non-regenerative) dehydration of insulating glass units, whether air filled or gas-filled.
7.Drying of refrigerants
Regeneration
Molecular sieve Type 3A can be regenerated by either heating in the case of thermal swing processes; or by lowering the pressure in the case of pressure swing processes.
To remove moisture from a 3A molecular sieve, a temperature of 200-230°C is required. A properly regenerated molecular sieve can give moisture dew points below -100°C.
The outlet concentrations on a pressure swing process will depend on the gas present, and on the conditions of the process.
Size
3A - Zeolites are available in beads of 1-2 mm, (10x18 mesh) 2-3 mm, (8x12 mesh) , 2.5-5 mm, (4x8 mesh) and as powder, and in pellet 1.6", 3.2".
Attention
To avoid damp and pre-adsorption of organic before running, or must to be reactivated.