How is 3A and 5A made from 4A Molecular Sieve?
Molecular sieve starts out as powder. The powder is then combined with a binding material. This allows the powder to be rolled into beads. These beads are partially dried at 600-700 degrees F, which turns them into a ceramic. In addition, all molecular sieve starts out as 4A, or the sodium form.
To make 3A molecular sieve, the manufacturers take the 4A molecular sieve powder and perform an ion exchange. This exchanges about half of the sodium ions in the structure with potassium ions, which changes the effective diameter of the pore openings and creates the 3A molecular sieve. There are different grades of 3A molecular sieve, which refers to the percentage of ions that are exchanged.
When turning 4A molecular sieve to 5A molecular sieve it is the same ion exchange process that occurs, but calcium ions are used instead.