Selection and Application for Molecular Sieve 13X
Time:2025-10-29
Molecular sieve 13X, also known as NaX molecular sieve, is an artificially synthesized crystal with a uniform microporous structure and a pore size of approximately 10 angstroms (Å). It is a key material in the field of industrial adsorption and separation. This article will provide an in-depth analysis of the classification, technical characteristics, and wide applications of 13X molecular sieves in different industries, helping you choose the most suitable solution for your process.
1、What is molecular sieve 13X?
Molecular sieve 13X belongs to the X-type zeolite molecular sieve, and its crystal structure consists of silicon oxygen tetrahedra and aluminum oxygen tetrahedra. The sodium ions (Na ⁺) in the skeleton can be exchanged with other cations, forming variants with different properties. The name "13X" comes from its initial cation being sodium and a pore size of 10 angstroms (International X-ray Classification).
2、Main classification and specifications of molecular sieve 13X
In order to meet the needs of different application scenarios, industrial 13X molecular sieves are usually subdivided based on their morphology, function, and cation type. This is crucial for your procurement decision.
1). Classified by shape:
*Raw powder: In powder form, mainly used as a catalyst carrier, additive, or raw material for further processing and shaping.
*Pellet or cylinder: Formed by extrusion, with a diameter typically ranging from 1.6mm to 3.2mm. It has low pressure drop and high mechanical strength, making it suitable for large fixed bed adsorption towers.
*Spherical or bead: Formed by sugar coating, with diameters typically ranging from 1.6-2.5mm and 3.0-5.0mm. Spherical particles have good flowability during loading, uniform bed distribution, and better wear resistance, which can effectively reduce the generation of dust when gas flows through.
2). Classification by function and cation exchange:
*Molecular sieve 13X APG: This is the most basic sodium based 13X model. It has a strong affinity for polar molecules such as water, carbon dioxide, and hydrogen sulfide.
*Main applications: deep drying air, natural gas, cracking gas; Simultaneously remove carbon dioxide and hydrogen sulfide.
*Molecular sieve 13X: Commonly used in the design of liquefied natural gas (LNG) processes. By optimizing the production process, it has a high co adsorption capacity for water and carbon dioxide, which can effectively prevent pipeline freezing and blockage in low-temperature environments. It is a key adsorbent in the LNG pretreatment process.
*Molecular sieve 13X HP: A molecular sieve specifically developed for pressure swing adsorption (PSA) oxygen production processes. Through special molding and activation processes, it has extremely high kinetic selectivity and can quickly adsorb nitrogen gas, allowing oxygen to pass through and achieve oxygen enrichment. Its mechanical strength and wear resistance have also been specially optimized to withstand frequent pressure changes in the PSA process.
*Lithium type molecular sieve: By exchanging some sodium ions (Na ⁺) with lithium ions (Li ⁺), its effective pore size can be reduced to about 8-9 Å. This variant is called "lithium exchange low silicon X-type molecular sieve" and has a higher nitrogen adsorption capacity.
*Main application: It is mainly used for VPSA oxygen production equipment with extremely high volume and efficiency requirements, such as aircraft cabin oxygen supply system (OBOGS) and medical oxygen production.
3、Core application areas of molecular sieve 13X
With its unique pore size and chemical properties, 13X molecular sieve plays an irreplaceable role in the following fields.
1). Oil and gas industry
*Natural gas purification: Before liquefaction or pipeline transportation, it is necessary to deeply remove water, CO₂, and H2S from the raw gas to prevent corrosion and freezing. Molecular sieve 13X is the preferred choice for this "purification" step.
*Refinery gas separation: Used to separate n-alkanes and isoparaffins from refinery gas to increase gasoline octane rating.
2). In the field of air separation and oxygen production
*Pressure swing adsorption (PSA) oxygen production: Molecular sieve 13X HP and lithium molecular sieve are the core of PSA oxygen production technology, widely used in metallurgy, chemical industry, glass manufacturing, sewage treatment, healthcare and other fields.
*Air pretreatment: Before the cryogenic air separation unit, 13X molecular sieve is used to deeply dry and remove CO₂ from the compressed air to protect downstream equipment.
3). Separation of Environment and Chemical Industry
*Carbon dioxide capture: Adsorption and separation of CO₂ from flue gas, biogas, or fermentation gas to assist in carbon reduction and resource utilization.
*Chemical process drying: used for deep drying of chemical raw materials such as olefins and refrigerants.
*Environmentally friendly adsorption: It can adsorb and remove harmful gases such as SO₂ and NOx from exhaust gas.
4、How to choose the right molecular sieve 13X for your application?
Choosing the correct molecular sieve 13X is the key to ensuring process efficiency and economic benefits. We suggest considering the following dimensions:
1). Target molecule: What are the main molecules that need to be adsorbed or separated? (Water, CO₂, N₂, H₂S, etc.)
2). Process type: Is pressure swing adsorption (PSA), temperature swing adsorption (TSA), or simply static drying used?
3). Operating conditions: What are the temperature, pressure, gas flow rate, and impurity concentration?
4). Equipment requirements: Is the adsorption tower design more suitable for strip or spherical packing? What are the requirements for dust and pressure drop?
Molecular sieve 13X, as an efficient and reliable adsorption and separation material, has been validated for its value through numerous industrial applications worldwide. Correctly understanding and selecting its subdivision types is the key to optimizing the process flow and reducing costs.
As a professional molecular sieve supplier, we can not only provide a full range of products from molecular sieve 13X, molecular sieve 13X-APG, and 13X, APG III to high-performance oxygen producing molecular sieve 13X HP, but also provide professional technical selection support and customized solutions according to your specific working conditions. Welcome to contact us anytime for free technical consultation and samples.
Air adsorption dryers are familiar in the chemical industry, and their core components are adsorbents , such as activated alumina, molecular sieves, silica gel. They adsorb water and gas through a porous structure, and their performance affects the drying effect directly. As the adsorption regeneration cycle progresses, the adsorption capacity gradually decreases and needs to be replaced regularly to ensure stable system operation.
The replacement cycle is usually 3-5 years, but it needs to be adjusted based on the following factors:
1. Frequency of use: High frequency use will accelerate the saturation of the adsorbent, and the cycle needs to be shortened; Long term high load operation will accelerate the decline of adsorbent performance;
2. Environmental humidity: The higher the humidity of the inlet air, the greater the adsorption load and the corresponding decrease in lifespan; High temperature, high dust and other harsh environments may require early replacement.
3. Operating parameters: Abnormal pressure or increased dew point temperature may indicate adsorbent failure.
Meanwhile, during work, it is important to pay attention to the following matters:
1. Monitoring indicators: Regularly monitor the dew point temperature at the outlet, and if it continues to exceed the standard, check the status of the adsorbent.
2. Replacement operation: Thoroughly clean the adsorption tower during replacement to avoid mixing of new and old adsorbents; The filling should be evenly compacted to prevent air flow short circuits.
3. Selection matching: The new adsorbent should be consistent with the prototype number to ensure that the porosity and mechanical strength meet the requirements.
4. Regeneration inspection: After replacement, verify the regeneration effect and confirm that the heating temperature and cooling time are normal.
So how to choose the right adsorbent for an adsorption dryer?
1) Molecular sieve: It is a crystal structure with uniform pore size and strong adsorption ability for water molecules, especially suitable for precision industrial scenarios with dew point below -60 ℃. However, due to its low strength, it is easy to be pulverization under high-intensity compressed air impact, so it can only be used in small quantities in traditional twin tower adsorption dryers.
2) Activated alumina: It is a high-strength adsorbent and the most widely used adsorbent in adsorption dryers currently. It can withstand the high-pressure impact of compressed air without powdering. Excellent performance in moderate humidity environments, suitable for places with dew point below -40 ℃, with a regeneration temperature 30-50 ℃ lower than molecular sieves.
3) Silica gel adsorbent: It’s getting less and less in compressed air drying. It is only suitable for drying at room temperature and is used in pressure dew point environments of -20 ℃.
In terms of drying performance, molecular sieves are much stronger than activated alumina, but the replacement cost is higher. Therefore, before choosing which adsorbent, it is necessary to understand the user's requirements or expectations for dew point, so as to choose the best solution that can meet the user's requirements and reduce the cost of use.
