Dehydration of Ethanol Using Molecular Sieves

For the catalytic reaction crystalline aluminosilicate salts of the molecular sieve family is used. Now let’s we look how molecular sieve will help in the dehydration of the ethanol.

The rectified spirit which is produced in the rectifier is superheated with steam in feed super- heater. After following this stage the super heated rectified spirit from the feed super heater is passes to one of the pair of molecular sieve bed for many times. Later by time the superheated rectified spirit vapor is poured or moved to another pair of bed. The loaded bed is regenerated by using a small portion of the anhydrous ethanol vapor leaving the fresh adsorption bed. Following this process a moderate vacuum pump operating after the condensation of the regenerated ethanol water mixture. The condensate is then transferred from recycle drum to the rectified column in the hydrous distillation plant by recycle pump. The remaining anhydrous absolute alcohol draw is again condensed in product condenser and passed to product storage.one of the main advantage of using this process is it cost less and also normally the molecular sieve has a life span of around five to seven years. While comparing azeotropic distillation this process cost very low.

Molecular Sieves are effective to remove moisture from Liquid!

Molecular sieves are excellent desiccants and are very effective in removing moisture from liquid, semi-liquid or gaseous substances. They are said to be even more effective than silica gel or activated alumina. The reason for their popularity is their crystalline composition which helps to create more moisture free products. Molecular sieves prove to be very useful in many cryogenic operations because this process requires gases to be converted into liquid form and in the process even a minute amount of water has to be extracted out in order to avoid freezing. According to the requirement you have different variants bases on its molecular size. As the molecular size increases it gets more surface area to absorb humidity. The variants available are 3A, 4A, 4A indicating molecular sieves, 5A and 13X.