How to use 4A molecular sieve? What are the requirements for the environment in which it operates? As a porous material, 4A molecular sieve is widely used in many fields because of its microporous molecular sieve as adsorption separation material, ion exchange material and catalytic material.
First, let’s take a look at the introduction of 4A molecular sieve:
Because its effective pore size is 0.4nm, it is called 4A molecular sieve, which can adsorb low molecular compounds such as water, methanol, ethanol, carbon dioxide, ethylene, sulfur dioxide, hydrogen sulfide, and propylene.
- 1. Molecular size of the method of using 4A molecular sieve
Because its effective pore size is 0.4mm, it cannot adsorb any molecule (including propane) with a diameter larger than 0.4mm, but its selective adsorption performance for water is higher than any other molecule, and it is one of the most widely used molecular sieve varieties in industry.
- The operating environment of the use method of 4A molecular sieve
1. When the temperature is 110°C, it is possible to evaporate the water in the large space, but it will not drive out the water in the pores of the molecular sieve. Therefore, in the laboratory, it can be activated and dehydrated by drying in a muffle furnace. The temperature is 350°C, and it is dried under normal pressure for 8 hours (if there is a vacuum pump, it can be dried at 150°C for 5 hours).
2. The activated 4A molecular sieve is cooled to about 200°C (about 2 minutes) in the air, and needs to be stored in a desiccator immediately.
3. In an allowed environment, dry nitrogen protection should be applied during cooling and preservation, which can effectively prevent the water vapor in the air from being adsorbed again. Because the old molecular sieve after use has contaminants, it should not only be activated at a temperature of 450°C, but also water vapor or inert gas (nitrogen, etc.) should be introduced to replace other substances in the molecular sieve.
4. Avoid oil and liquid water when using, and try to avoid direct contact with oil and liquid water.
As an alkali metal aluminosilicate, 4A molecular sieve is favored by many customers in the drying of gas and liquid, and can also be used for refining and purification of gas or liquid, such as extraction of argon. Now, do you understand the precautions for its use?
Browse more molecular sieve knowledge:
https://www.kelleychempacking.com/news/adsorption-performance-of-4a-molecular-sieve-for-h%e2%82%82s/
https://www.kelleychempacking.com/news/2-tips-to-extend-the-life-of-molecular-sieves/
https://www.kelleychempacking.com/news/korean-customer-inspected-the-production-schedule-of-80-tons-of-molecular-sieve/
Post time: Nov-04-2022