Molecular Sieve Adsorbents – What They Are & How They Work

Molecular sieve adsorbents are synthetic zeolites that have many tiny pores of the same size. They can adsorb molecules to an extent of 20 to 25% of their mass.

Molecular sieve adsorbents are useful because they can hold a lot of molecules, choose the ones they want, last long, and can be reused. Mainly made up of 3-D structures of Alumina oxide and Silicon Dioxide, molecular sieves can be used for removing contaminants, moisture, air, or unsuitable molecules from different substances.

Types of Molecular Sieve Adsorbents

Molecular Sieve 3A

Molecular Sieve 3A is a potassium-infused form of zeolite A, having a pore size of 3 angstroms. It can adsorb water and molecules sized less than 3 angstroms, Therefore, it can be used to suck water out of both liquids and gases, like methanol, ethanol, natural gas, refrigerants, and air. You can reuse Molecular Sieve 3A after heating it to 250 º C to get rid of any leftover moisture.

Sorbchem India provides the largest molecular sieve range available in India, supplied in a dry environment and controlled conditions in beads, pellets, and powder forms.

Molecular Sieve 4A

Meet Molecular Sieve 4A, a sodium form of zeolite A, having a pore size of 4 angstroms. Therefore, it can adsorb water and other molecules equal to or smaller than 4 angstroms, like oxygen, nitrogen, and carbon dioxide, and suck moisture out of air, solvents, and pharmaceuticals products.

Molecular sieve 4A can also be used to purify and separate liquids and gases, such as argon, krypton, xenon, hydrogen, and oxygen. If you want to regenerate Molecular Sieve 4A, heat it to temperatures between 250f to 450f

Molecular Sieve 5A

Next up, the formidable Molecular Sieve 5A with a pore size of 5 angstroms. It is a calcium form of alkali alumina silicate and is the most suitable for Pressure Swing Adsorption.

Molecular Sieve 5A can capture a variety of molecules, ranging from water and carbon dioxide to alcohols, mercaptans, and hydrocarbons. It is mostly used for paraffin separation, removing moisture and hydrocarbon from SF6 refrigerant, and for the Pressure Swing Adsorption process of oxygen or hydrogen.

Molecular Sieve 13X

Molecular Sieve 13X has a 10 Angstrom pore size, which is bigger than the 3A, 4A, and 5A variants. Therefore, it filters out any molecules larger than the kinetic pore diameter of 10 Angstrom. It adsorbs water, carbon dioxide, alcohol, aromatics, and hydrocarbons, along with purifying liquids and gases like air, natural gas, oxygen, and nitrogen.

Molecular Sieve 13X can be reused after heating it at a temperature of 260-320 degrees, and then cooling it to room temperature. Pressure swing adsorption is another method to regenerate the molecular sieve 13X, or purging the sieve in a pure medium liquid or gas would also do the trick.

Carbon Molecular Sieve

The Carbon Molecular Sieve, crafted from carbonized organic polymers, flaunts its adaptability with variable pore sizes and high attraction to oxygen and carbon molecules. With a high Nitrogen Yield, it is highly useful for all PSA Nitrogen Systems – quickly separating oxygen from compressed air and leaving behind nitrogen. It has a unique ability to adsorb hydrogen, methane, and carbon monoxide based on their kinetic diameters.

Molecular Sieve Powder

Activated molecular sieve powder is a form of 3A and 4A molecular sieve that is utilized for a variety of specialized adsorbent purposes like scavenging the moisture evolved during formulation of 1 K, 2 K or 3 K Epoxy Resin , Paints or Polyurethane Systems  and balancing the basic chemicals in paint. Sorbchem India provides pure molecular sieve powder with high adsorption quality and efficacy.

Advantages Of Molecular Sieve Adsorbents

Molecular sieve adsorbents are widely utilized to achieve molecular separation based on size.

• High adsorption capacity: These adsorbents can remove large quantities of water/moisture and polar molecules from liquids or gases, thus boosting the purity and quality of the product.

• Stability and resistance: Molecular sieve adsorbents resist challenging conditions, including high temperatures, pressures, and exposure to contaminants. As a result, they are highly durable and optimal in performance.

• Regeneration: Molecular sieve adsorbents can be reused. You just have to apply heat or gas and wait for the adsorbed molecules to be removed.

The Pressure Swing Adsorption (PSA) procedure is a popular regeneration procedure, where one molecular sieve bed is dehydrated, and the other is regenerated under a vacuum. The resultant water from one bed is mixed with the vapors from the other bed, turned into liquid, and then pumped out.

How To Choose The Right Molecular Sieve Adsorbent?

Choosing the right type of molecular sieve adsorbent for your needs can be challenging, but here are some tips or recommendations to help you:

You must note the size and shape of the molecules you want to remove or keep. Different kinds of molecular sieve adsorbents have different pore sizes, ranging from 3 to 10 angstroms.

Think about how much and how well the molecular sieve adsorbent can hold and let go of molecules. For example, if you want to make compressed air dry, you should use a molecular sieve, which can hold more molecules than activated alumina, and can make the air very dry at low moisture levels.

Test the strength of the molecular sieve adsorbent in terms of handling high heat, pressure, and dirt. You should pick the kind that can survive the situation of your need without fault.