Molecular Sieve Adsorbents Basics

ZEOCHEM® Molecular Sieves

Manufactured in Switzerland and in the United States.

Molecular sieve adsorbents are crystalline alumino-silicates. Their unique structure allows the water of crystallization to be removed, leaving a porous crystalline structure. These pores or "cages" have a high affinity to and re-adsorb water or other polar molecules. Aided by strong ionic forces (electrostatic fields) caused by the presence of cations such as sodium, calcium and potassium, and by the enormous internal surface area of close to 1'000 m2 / g, molecular sieves will adsorb a considerable amount of water or other fluids. If the fluid to be adsorbed is a polar compound, it can be adsorbed with high loading even at very low concentrations of the fluid.

Molecuar sieves will therefore remove many gas- or liquid impurities to very low levels (PPM or less).

Another feature of molecular sieve adsorbents is their ability to separate gases or liquids by molecular size or polarity. The pore or "cage" openings are of the same size as many molecules. e.g. in the case of hydrocarbon paraffins, the normal, straight chained molecules can fit into the pores and be adsorbed, while the branched chain molecules cannot enter the pores and pass through the molecular sieve bed un-adsorbed.

The Zeochem molecular sieve adsorbents product range includes all commercially used types, such as 3A, 4A, 5A and 13X, as well as several special types, formulated for specific applications. (e. g. VOC adsorption by ZEOcat® products).

For typical characteristics, chemical- and physical properties of the various Zeochem molecular sieve adsorbents and further information on their nature, applications etc. please check with our ZEOCHEM product portfolio brochure or contact Zeochem AG.