Why is the molecular sieve used in our purifier 13X?

This post was last edited by rzs20000 on 2012-5-15 09:36. The 5A molecular sieve has a pore size of 5A, allowing it to adsorb any molecules smaller than this pore size. It is primarily used for the separation of ortho and iso hydrocarbons, as well as for the coadsorption of water and carbon dioxide. Given the industrial applications of 5A molecular sieves, they feature high selectivity and fast adsorption rates, making them particularly suitable for pressure swing adsorption processes. They can be used in pressure swing adsorption units for producing oxygen, hydrogen, carbon dioxide, and other gases, regardless of their scale, and thus represent top-quality products in the field of pressure swing adsorption. Molecular formula: 0.70CaO·0.30Na2O·Al2O3·2.0SiO2·4.5H2O
Properties, Unit, Technical Specifications:
Shape: Rod, Sphere
Diameter, mm: 1.5–1.7, 3.0–3.3, 2.0–3.0, 3.0–5.0
Particle size percentage: ≥98, ≥98, ≥96, ≥96
Bulk density, g/ml: ≥0.60, ≥0.60, ≥0.60, ≥0.60
Wear rate percentage: ≤0.20, ≤0.25, ≤0.20, ≤0.25
Compressive strength, N: ≥30/cm, ≥45/cm, ≥30/p, ≥60/p
Static water adsorption percentage: ≥21.5, ≥21.5, ≥21.5, ≥21.5
n-Hexane adsorption percentage: ≥14, ≥14, ≥14, ≥14
The pore size of 13X molecular sieve is 10A; it can adsorb any molecules smaller than 10A. It can be used as a co-catalyst support, for the simultaneous adsorption of water and carbon dioxide, as well as water and hydrogen sulfide gas. It is primarily used in the drying of pharmaceuticals and air compression systems. Different specialized variants are available for various applications. Performance parameters of 13X molecular sieve Performance parameters of 13X molecular sieve Property, Unit, Technical specification, Brand, Shape: Strip, Sphere. Transung. Diameter, mm: 1.5–1.7, 3.0–3.3, 1.0–1.6, 3.0–5.0. Transung. Particle size percentage: ≥98, ≥98, ≥96, ≥96. Transung. Bulk density, G/ml: ≥0.54, ≥0.54, ≥0.60, ≥0.60. Transung. Wear rate percentage: ≤0.20, ≤0.25, ≤0.20, ≤0.20. Transung. Compressive strength, N: ≥30/cm, ≥45/cm, ≥10/p, ≥60/p. Transung. Static water adsorption percentage: ≥25, ≥25, ≥25, ≥25. Transung. Carbon dioxide treatment capacity per gram of air, NL/g: ≥14, ≥14, ≥14, ≥14. Transung. Water content in packaging, %: ≤1.5, ≤1.5, ≤1.5, ≤1.5. Applications of 13X molecular sieve: 1) Gas purification in air separation units, to remove water and carbon dioxide. 2) Drying and desulfurization of natural gas, liquefied petroleum gas, and liquid hydrocarbons. 3) Deep drying of general gases. Water content in packaging, %: ≤1.5, ≤1.5, ≤1.5, ≤1.5

5A molecular sieve is a calcium silicoaluminate. The uniform pore size is approximately 5×10-7 mm, the bulk density is 700–800 kg/m3, the specific surface area is 750–800 m2/g, the porosity is 47%, and the mechanical strength is greater than 95%. Its water adsorption capacity is about 21.5%, while its carbon dioxide adsorption capacity is 1.5%. It exhibits coadsorption of hydrocarbons such as acetylene alongside the adsorption of water and carbon dioxide. 13X molecular sieve is a sodium-type silicoaluminate with a uniform pore size of approximately 10×10-7 mm, a bulk density of 600–700 kg/m3, a specific surface area of 800–1000 m2/g, a porosity of 50%, and mechanical strength greater than 90%. Its water adsorption capacity is about 28.5%, while its carbon dioxide adsorption capacity is 2.5%. In addition to absorbing water and carbon dioxide, it also exhibits coadsorption properties for hydrocarbons such as acetylene. Compared with the two adsorbents, the adsorption performance of 13X molecular sieve is superior to that of 5A molecular sieve. However, the mechanical strength and wear resistance of 13X molecular sieves are slightly lower, and their manufacturing process is more complex, resulting in higher prices. The molecular sieve purifier of small oxygen generators operates at a relatively high pressure, with a normal pressure of 1.5–2.5 MPa and a starting pressure of 5.0 MPa. The operating cycle of oxygen generators is short (3–6 months), and after the air is processed through a molecular sieve purifier, its carbon dioxide content must be less than 5×10-6. Therefore, in the past, 5A molecular sieves were commonly used in medium-pressure molecular sieve purifiers. Currently, to extend the operating cycle of oxygen generators, 13X molecular sieve is also being used as the adsorbent in medium-pressure purifiers. Due to the low operating pressure (0.5–0.6 MPa) of large-scale fully pressurized oxygen generators, the dynamic adsorption capacity of molecular sieves for moisture and carbon dioxide decreases. Moreover, these large oxygen generators have a long operational cycle (usually two years), which requires that the carbon dioxide content in the air after purification be less than 1×10-6. In order to reduce the amount of molecular sieve needed, 13X molecular sieves are used in all low-pressure molecular sieve purifiers. That’s what it says in the questions and answers for oxygen producers.

It really says that above, hehe. Thank you. I just find it strange that it compares 5A and 13X above. And then there was such a saying