When aggressive moisture adsorption is required in industrial or commercial applications,molecular sieves are often used.These powerful desiccants can be used in order to remove any traces of moisture from a given environment,provided they are used in the right quantity.Some of the common examples of the use of such a desiccant would be in electronic products as well as pharmaceutical products where any traces of moisture could harm the circuits.
What gives this desiccant a high adsorption quality is the presence of an intricate network of pores and empty cavities where moisture or vapors can be adsorbed.The pore sizes of this desiccant are measured in a unit called Angstroms.Molecular sieves are available in versions such as 3X,4X,5X,10X etc.The higher the numerical value,the better are the adsorption capabilities.The chemical name of this desiccant is Synthetic Sodium Potassium or Calcium Aluminosilicate.
There are several desirable attributes of this particular desiccant that make it an ideal choice for use in demanding applications.Here are a few traits of this desiccant:
The melting point of this desiccant is slightly less than 2900 degrees Fahrenheit.
It is an odorless desiccant which means that it can easily be used with food products as well as pharmaceutical products.
Also,it demonstrates a negligible fire and explosion hazard,making it safe for use in different types of high temperature applications too.
Chemically too,this is a very stable material which means that it won't react with other substances.
Workers handling this desiccant aren't exposed to any known chronic health hazards.OSHA,NTP or IARC has not listed it as a carcinogen.
The only precautions one needs to take while handling this material is the proper use of masks and gloves as eye or skin contact could cause irritation.It should be handled in an area where there is appropriate ventilation.
Considering these points,it is clear that molecular sieves are one of the most easy to handle desiccants.However,given their aggressive adsorption properties,they are also among the more expensive desiccants to procure.This desiccant is usually sold in the form of opaque tan or beige beads.When packaged in the appropriate materials,these desiccant packets can be placed along with several different products.
There are several firms that are engaged in continued research relating to newer applications of this desiccant.Since molecular sieves have the ability to adsorb up to 20%of their own weight,they can be used for extended moisture control applications.In fact,some studies have shown that these desiccants can be effectively used in various applications to bring down the relative humidity to as low as 10%.