Molecular Sieve

Molecular sieve desiccant is an alkali alumino-silicate. It is the sodium form of the Type A crystal structure and has an effective pore opening of 4 angstroms.

A common application of silica gel molecular sieve is dehydrating compressed air via a molecular sieve dryer. In an air dryer molecular sieve is regenerated by heating and purging. Regeneration temperatures must be 400° to 600° F, but are not to exceed 1000° F. The degree of regeneration depends on the temperature reached in purge. Molecular sieve is often used as a polishing layer in air dryers to reach dewpoints of -120° F.

Molecular Sieve Features

• Dewpoints Down to 100° F. and Lower: molecular sieves are often used as a polishing layer in molecular sieve dryers to achieve dewpoints down to -120°F. Molecular sieve is the most effective desiccant for low inlet, relative humidities, generally below 30-35% RH.
• Uniform Size = Low Pressure Drop in a packed bed, molecular sieve provides a low pressure drop which minimizes channeling and maximizes utilization of the whole drying capacity of the compressed air dryer tower.
• Round Smooth Beads/Low Abrasion: This feature of molecular sieves also contributes greatly to lower pressure drop. Importantly, it means far less dusting, migration / attrition and longer life by not allowing clogging of desiccant pores.