Water and moisture can play a very inconvenient role in various industrial areas. In order to purify some industrial products like different gases and liquids, removing the water or moisture becomes very important. In order to successfully complete this process, molecular sieves desiccants are used. In fact, the application of these molecular sieves has flourished massively over the last few years. These crystal compositions make it easier to absorb the moisture and other impurities and possess the pure gas or liquid. This process is much more convenient and easier compared to other procedures. The application of these sieve desiccants is seen in the industries like pharmaceutical, petrochemical, food, gas, transportation etc.
Mostly four types of molecular sieve desiccants are used in the industrial areas which are 3A, 4A, 5A and 13X sieves. These sieves are available in the form of pellets, powder and beads. Each of these molecular sieves has their different usage and importance in the industrial area. Molecular sieve is mainly used for water removal. However, the usefulness of these sieves depends on the diameter size and polarity of the sieves. These functions include natural gas drying, glass dehydration, solvent drying, oxygen purification, mercaptan remove etc.
Let’s have a look at each of those molecular sieve desiccants. I shall start with the 3A molecular sieve.
The use of this molecular sieve is mostly seen in the alcohol or spirit making industry. In most of the industries Ethanol is required to be 100% water free. The finally manufactured alcohol is basically 94% alcohol and rest of the percentage is water. Removing the water from alcohol using any conventional method is very difficult. But with the help of molecular sieve 3A, this can be done very conveniently.
This molecular sieve is used in various industries. In this process molecules with 4A0 pore size are used for the adsorbing process. This clearly means that molecules with more than 4angstrom pore size cannot be absorbed by this process. These molecular sieves are perfect for removing water or moisture from liquids or gasses.
As per the structure this molecular sieve is an alkali alumino silicate carbon. It is available with pore size 5A0 or 5 angstrom. These sieves can absorb the molecules with pore size smaller than 5A. It can also absorb molecule with diameter more than 5A. The key use of this type of molecule sieve is to separate isomerous alkane from the normal ones.
The key applications of this molecular sieve are drying commercial gas, purification of air plant feed, sweetening of natural gas and hydrocarbon.
Molecular Sieves 