What is molecular sieve?
Molecular sieve is a kind of aluminosilicate compound with cubic lattice. It mainly consists of aluminosilicate connected by oxygen bridge to form an empty skeleton structure. In the structure, there are many uniform pore channels and well-arranged holes with large inner surface area. In addition, it contains metal ions with lower electricity price and larger radius of ions and hydrated water. Because the water molecule loses continuously after heating, but the crystal skeleton structure remains unchanged, many cavities of the same size are formed, and the cavities are connected by many micro-holes of the same diameter. These micro-holes are uniform in diameter and can absorb molecules smaller than the diameter of the channel into the inside of the hole, while larger molecules than the channel. Because of exclusion, molecules with different shapes and diameters, polarity, boiling point and saturation can be separated, which is called molecular sieve.
The role of molecular sieves:
At present, molecular sieves are widely used in chemical, electronic, petrochemical, natural gas and other industries.
Molecular sieve models commonly used in gas industry:
Type A: potassium A (3A), sodium A (4A), calcium A (5A)
Type X: Calcium X (10X), Sodium X (13X)
Type Y: Sodium Y, Calcium Y
Molecular sieves have strong hygroscopicity and should be used for purification of gases. When preserved, direct exposure to air should be avoided. Molecular sieves with long storage time and moisture absorption should be regenerated before use. Molecular sieves avoid oil and liquid water. Avoid contact with oil and liquid water when using. In industrial production, the drying gases are air, hydrogen, oxygen, nitrogen, argon and so on. Two adsorption dryers are connected in parallel, one working, and the other can be regenerated. Alternate work and regeneration to ensure continuous operation of equipment. The dryer works at room temperature and regenerates by flushing air at
350 C.
Can molecular sieves be cleaned?
Molecular sieve is a reusable aluminosilicate compound, which is very vulnerable to acid and alkali damage. It is generally not recommended to clean it. If water-soluble substances can be washed with clean water, then dried in a drying box at
150 degrees for one hour, then roasted in a high temperature muffle furnace at
500-550 degrees for one hour, the crystalline water can be removed and regenerated. That's it.