FAQ

3A, 4A, 5A, and 13X molecular sieves have different effective pore sizes, which are 0.3nm, 0.4nm, 0.5nm, and 1nm respectively, and their application scenarios are also different. 3A is used for ethanol drying, 4A is used for deep gas dehydration and drying, 5A is used for oil and natural gas drying, and 13X is used for adsorption of impurities in air separation and purification devices.

The difference is that molecular sieve powder is the single raw material for producing molecular sieves, which has low activity and cannot absorb water. Activated molecular sieve powder is a powder with adsorption activity produced by adding specific additives and dehydrating at high temperature.

Molecular sieve selectively adsorbs based on molecular size and polarity. The interior of its crystal pores has strong polarity and Coulomb field, and has strong adsorption capacity for polar molecules and unsaturated molecules. Only substances with molecular diameters smaller than the pore diameter can enter the crystal pores.

- Polar adsorption: The surface of the molecular sieve has a certain polarity. For polar molecules or polarizable molecules, they can have a strong effect on the surface of the molecular sieve, or induce the polarization of the molecules to produce strong adsorption, while non-polar molecules are not easily adsorbed.

Common regeneration methods include heating regeneration and decompression regeneration. Heating can desorb the adsorbed substances, and decompression can reduce the partial pressure of the adsorbate on the surface of the molecular sieve to promote desorption. However, regeneration requires good control of temperature, pressure and other conditions to ensure that the performance of the molecular sieve is not damaged.