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How to use Molecular sieves to dry an organic solvent?

How to use Molecular sieves to dry an organic solvent? Also, how to recover the Molecular sieves after use? Thanks for help. Appreciate if can provide related reference.

Best Answer:  Molecular sieves are a type of zeolite. Zeolites are porous minerals; these pores are very small, on the order of angstroms. 
In organic chemistry, 4A (angstrom) molecular sieves are often used. They must first be dried in an oven to remove water obtained from storage. Some people insist on using a vacuum oven--I cannot say for sure if this is necessary. After cooling in a dessicator, they are ready to use. 
I have used mol. sieves mostly as a way to remove water during reactions in which water is produced but is harmful to the product, or to drive the reaction forward (Le Chatalier's principle - removing a product drives reaction forward). However, you can also distill solvents using molecular sieves. Simply place them in the round-bottom flask with the solvent. The sieves will trap the water, so the distillate will not have any water in it. 

I think you can reuse them by redrying them. Let the organic solvent evaporate, then place in the oven. As a note of caution, molecular sieves give off "dust" slowly, so I wouldn't reuse them indefinitely, as they turn the solvent cloudy. If you aren't sure about this, there are chemical methods of drying organic solvents. Armarego's Purification of Organic Compounds contains appropriate reagents for different solvents.