Molecular sieves are zeolites. Zeolites are crystalline three-dimensional aluminosilicates with cavities inside the crystal lattice. These cavities are connected by channels, the so-called pores. The pores have an exactly defined diameter which is the most important parameter for the application of zeolites. That means just molecules having a diameter smaller than the diameter of the pores reaching the cavities. Thereby an accurate separation (selectivity, molecular sieve effect) between absorbable and non-absorbable molecules is possible.
According to their pore Grade like 3A, 4A, 5A and 13X are available in Beads and Pellet Forms.
Yes, you can regenerate. There are some methods of Regeneration of Molecular Sieve include pressure change, heating and purging with a carrier gas or vacuum Pressure Swing Adsorption. Regeneration temperatures depend on Molecular Sieve type
Life of Molecular Sieves is around 5-6 years. However, Molecular Sieves life is reduced by oil and any other impurities in the air. Therefore, it is essential to provide special pre-filters if lubricated air is used.
5) What is the difference between the various molecular sieves? How to select the Molecular Sieve properly?
- The main difference between them is pore size. The nominal pore sizes for 3A, 4A, 5A, and 13X are 0.3, 0.4 and 0.5 nanometers, respectively.
- 3A is mainly applied to absorb water molecules in drying natural gas and oil gases, especially in drying Catalytic Splitting Decomposition Oil gases and Alkenes.
- 4A is mainly used to make dehydration in a liquid system or airtight gas. In addition, it can also remove the molecules of hydrogen sulfide, ethyl alcohol, carbon dioxide, and ethylene.
- 5A is mainly used to separate the isomerism alkanes. Meanwhile, it can also able to absorb the molecules which can pass through Molecular sieve 3A and molecular sieve 4A and whose diameters are less than 0.5 nm.
- All molecules which can be absorbed on Sieve Types 3A, 4A, and 5A can be adsorbed on sieve Type 13X. In addition, sieve Type 13X can adsorb molecules of larger diameters, such as branched-chain hydrocarbons and aromatics.