How 3A & 4A desiccants work for solvent drying?
The desiccants with different types of beads and pellets forms are required based on the molecular sizes, polarity and particular needs. Like, 3A molecules are used to dry solvents such as ethanol, methanol and acetone. Similarly, 4A molecules are used as the adsorption agent for benzene, carbon tetrachloride, chloroform, dimethyl sulfoxide, Toluene, Xylene etc. They can strongly adsorb the water and can control the pore sizes effectively. In order to separate the molecules based on their different molecular diameters, such type of crystalline synthetic zeolites are used for keeping the solvents dry. The higher adsorption speed, excellent anti-contaminative resistance and longer working ability make them the perfect desiccants for solvent drying operation.
In the drying process, the solvent is passed through the columns of molecular sieve. Both the water and solvent are adsorbed at the surface of molecular sieves. The smaller water molecules can be easily resided in the large surface area within the pores and get removed from the solvent. Therefore, solvents can be dehydrated using the desiccants based on their efficiency and molecular size.They can be regenerated and reused from most applications by heating them at the certain temperature.