What is molecular sieve? Where is it used and what are its features?
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Molecular sieve are crystalline metal aluminosilicates with a three-dimensional interconnected silica and alumina tetrahedra network.
Natural hydration water is heated away from this network to produce homogeneous cavities that selectively adsorption molecules of a specific size.
Molecular sieves are synthetic zeolite materials designed with precise and uniform structure and size pores. This also provides adsorb gases and liquids, preferably based on molecular size and polarity. Zeolites are naturally existing, highly porous crystal solids belong to the class of chemicals known as aluminasilicates.
Selection of molecular sieves
Molecular sieves are available in different shapes and sizes. However, spherical beads have advantages over other shapes because they offer low pressure drops, are resistant to wear and good strength because they have no sharp edges, so the crushing force required per unit area is higher. Some beaded molecular sieves offer lower heat capacity, so they offer a lower energy requirement during regeneration.
Another advantage of using beaded molecular sieves is that the stack density is usually higher than the other way, so the molecular sieve volume required for the same adsorption requirement is less. So you can use beaded molecular sieves, install more adsorbans of the same volume and avoid any ship modifications when disinfecting.
What are the types of molecular sieves?
There are four main types of molecular sieves: 3A, 4A, 5A, and 13X. The type depends on the chemical formula of the molecule and the molecular sieve determines the size of the pore. The molecular sieve works by adsorbing gas or liquid molecules that are effectively diameter than pores, except for those molecules with larger openings. The molecular sieve, which is related to our field, is 3A type. The molecular sieve used in insulation glass is known as 3A.
3å molecular sieve, adsorb molecules with diameters greater than 3 Å. The fast pace of adsorption of these molecular sieves, reesken frequently, well breaking and pollution and pollution and tell. These properties have both sieve sieves and this. 3s molecular sieves are drying in the gasoline, polymerization and chemical gas-liquid dry refined petroleum and chemical industries.
It used and Its features
| Model | Pore diameter (Ångström) | Bulk density (g/ml) | Adsorbed water (% w/w) | Attrition or abrasion, W (% w/w) | Usage |
|---|---|---|---|---|---|
| 3Å | 3 | 0.60–0.68 | 19–20 | 0.3–0.6 | Desiccation of petroleum cracking gas and alkenes, selective adsorption of H2O in insulated glass (IG) and polyurethane |
| 4Å | 4 | 0.60–0.65 | 20–21 | 0.3–0.6 | Adsorption of water in sodium aluminosilicate which is FDA approved (see below) used as molecular sieve in medical containers to keep contents dry and as food additive having E-number E-554 (anti-caking agent); Preferred for static dehydration in closed liquid or gas systems, e.g., in packaging of drugs, electric components and perishable chemicals; water scavenging in printing and plastics systems and drying saturated hydrocarbon streams. Adsorbed species include SO2, CO2, H2S, C2H4, C2H6, and C3H6. Generally considered a universal drying agent in polar and nonpolar media;[12] separation of natural gas and alkenes, adsorption of water in non-nitrogen sensitive polyurethane |
| 5Å-DW | 5 | 0.45–0.50 | 21–22 | 0.3–0.6 | Degreasing and pour point depression of aviation kerosene and diesel, and alkenes separation |
| 5Å small oxygen-enriched | 5 | 0.4–0.8 | ≥23 | Specially designed for medical or healthy oxygen generato | |
| 5Å | 5 | 0.60–0.65 | 20–21 | 0.3–0.5 | Desiccation and purification of air; dehydration and desulfurization of natural gas and liquid petroleum gas; oxygen and hydrogen production by pressure swing adsorption process |
| 10X | 8 | 0.50–0.60 | 23–24 | 0.3–0.6 | High-efficient sorption, used in desiccation, decarburization, desulfurization of gas and liquids and separation of aromatic hydrocarbon |
| 13X | 10 | 0.55–0.65 | 23–24 | 0.3–0.5 | Desiccation, desulfurization and purification of petroleum gas and natural gas |
| 13X-AS | 10 | 0.55–0.65 | 23–24 | 0.3–0.5 | Decarburization and desiccation in the air separation industry, separation of nitrogen from oxygen in oxygen concentrators |
| Cu-13X | 10 | 0.50–0.60 | 23–24 | 0.3–0.5 | Sweetening (removal of thiols) of aviation fuel and corresponding liquid hydrocarbons |
How is molocular sieve used in insulation glass?
Molecular sieve 3A particles are widely helpful in drying the interior of the insulation glass to help protect insulated glass units due to their high water retention capacity and better physical properties. They are mainly used in the smooth, clean and transparent appearance of glass, even at very low temperatures. Figure 3A molecules have the ability to adsorb water as hollow glass dryer and to significantly ensure the life of hollow glass windows. Molecular sieve 3A in the form of beads in various series can be used to absorb moisture and prevent the flow of glass without freezing or damaging the glass surface.
This type of dryer is highly appreciated in the construction of energy-efficient houses or buildings. The window caused by inflation can solve the problem of deterioration and contraction occurs in different seasons or during the day at different temperatures.