Sciencemadness Discussion Board

Drying Crystals without oven

Yttrium2 - 2-10-2022 at 17:46

Can this always be done?
Is there anytime an oven needs to be utilized to dry hygroscopic crystalline salts?

Bedlasky - 2-10-2022 at 22:22

Have you ever heard about desiccator and vacuum desiccator?

Lionel Spanner - 4-10-2022 at 11:34

Another method is azeotropic distillation of the water; useful for substances like oxalic acid, which sublimes at around 155 °C and has a significant vapour pressure above 100 °C.
If the distillation is done under reduced pressure, the temperature can be reduced further.

Mateo_swe - 5-10-2022 at 15:26

You need a desiccator (or a DIY replacement) and a drying agent like anhydrous Epsom salt or NaSO4.
Heat and vacuum is optional in most cases but it dries faster using it.

j_sum1 - 5-10-2022 at 16:01

For low tech, make a desiccator bag.

Use a large zip-lock bag or an air-tight plastic container. Pop a desiccator in there as well as your material to be dried – both on a shallow dish. Leave for a long time. Come back later and your material should be a lot drier.
Suitable desiccators are concentrated H2SO4 or CaCl2 (pool grade is satisfactory). NaOH or KOH probably also work, although I admit that I have never used them. I have many other uses for these bases and don't use them for trivial drying tasks.

Alternatively, buy a cheap toaster oven. Mine gets quite regular use for drying glassware and small batches of some compounds.

Yttrium2 - 6-10-2022 at 21:02

To be more clean, elaborating, direct, succinct, and frank,

No utility hook ups may be used in the H3PO3 isolation challenge :)

That’s why there is no oven***
In addition to mag stirring
Vacuum.

Can it be done?

Yttrium2 - 6-10-2022 at 21:05

Additionally H3PO3 reacts with lots of drying agents.


Does that mean desiccant too? Or is more hygroscopic, so it won’t be dried.


Why?

[Edited on 10/7/2022 by Yttrium2]

Yttrium2 - 8-10-2022 at 11:25

Quote: Originally posted by j_sum1  
For low tech, make a desiccator bag.

Use a large zip-lock bag or an air-tight plastic container. Pop a desiccator in there as well as your material to be dried – both on a shallow dish. Leave for a long time. Come back later and your material should be a lot drier.
Suitable desiccators are concentrated H2SO4 or CaCl2 (pool grade is satisfactory). NaOH or KOH probably also work, although I admit that I have never used them. I have many other uses for these bases and don't use them for trivial drying tasks.

Alternatively, buy a cheap toaster oven. Mine gets quite regular use for drying glassware and small batches of some compounds.


H2S04 reacts with H3PO3, is it really suitable for drying H3PO3 if it does not make contact, or would the fumes interact?