silica gel or molecular sieve

[processengineer1998]

Hi
I want to know the criteria for selection of silica gel or molecular sieve for dehydration of gas.
what are advantages and disadvantages of each process in design,operation and cost standpoints.

 

[MortenA]

Molecular sieves have a higher capacity (which holds better at temperatures above 38 °C) and are more versatile than other desiccants butthey are also more expensive

At temperatures below 38 °C, no decrease in adsorption capacity is expected and therefore the use of silica gel would be more appropriate given the lower price (both in desiccant volume and operation costs).

Best regards

Morten

 

[dcasto]

Silica Gels don't have quit as low of equilibrium and therefore will not get dew points below -50F as readily as a mole sieve can.