Sciencemadness Discussion Board

Drying Calcium Chloride Safely after soaked in Diethyl Ether?

LuckyWinner - 5-9-2020 at 06:43

I want to reuse my calcium chloride that was soaked with water inside my diethyl ether for a while.
reeks a bit of ether after taking it out of the emtpy ether bottle.


quote from SM member about mol sieves:

'Don't put flammable solvents in the oven.
:o
It's a good idea to leave the used stuff exposed to air, outside or somewhere well ventilated for a while, then soak it with water and let it dry in air before slowly drying in an oven.'


since calcium chloride quickly becomes a puddle if too long exposed to air...
what would be the proper procedure for calcium chloride to dry it if you have a cheap pizza oven from the supermarket that goes to 220C max?

which was previously soaked in ether

outer_limits - 5-9-2020 at 07:06

I would leave it for a while in well ventilated area near ventilator blowing the air on it. Ether should be easy to remove and it shouldn't take long.

LuckyWinner - 5-9-2020 at 07:10

Quote: Originally posted by outer_limits  
I would leave it for a while in well ventilated area near ventilator blowing the air on it. Ether should be easy to remove and it shouldn't take long.


and after, dry it the same way like mag sulfate (nilred video)
https://youtu.be/CKTjXXtv6w8

1 hour at 110C
move around in baking pan
then raise temp to 120C, till it appears dry
then 150C , till it appears dry
then 180C, till it appears dry
then 200C, till it appears dry
then 220C (limit of my oven)

till it appears bone dry.

are all these small incremental heating ups necessary with
calcium chloride?

Fyndium - 5-9-2020 at 10:52

When I dried CaCl2 flakes, I just blasted them at full power at 300C my oven max. They did not change appearance at all, actually, which was surprising, because the bag states they're 77%.

When I dried Ca sulfate as gypsum, I put a thermoprobe into it. A pan of 1kg of CaSO4 gypsum heated up, and it plateau'd at certain temperatures, and it appears to me that a dehydration of a kind occurs at such temp. I did not record the plateaus. I heated it up to 230C as per drierite regeneration instructions.

Flammable solvent soaked desiccants speaking, I would at first spread them thinly in a well ventilated space like outdoors and let them evaporate a good day or two before ovening them.

Fyndium - 7-10-2020 at 12:50

I needed to dry some acetone soaked powder but was afraid of detonating my oven. So I figured I place thermal mass of steel plate and heat it up so its well below autoignition and then let the heating elements cool a little and put the stuff in the oven. The big plate stays hot for hours.

woelen - 8-10-2020 at 23:36

Ether is very volatile. I simply would put it outside in air for a while and once it looks reasonably dry, then put it in the oven. You can test the presence of ether by smelling it. Even a low concentration of ether can be smelled easily. If the smell of ether is absent (or very weak), then you can put it in the oven safely.

If your climate is very humid, then the CaCl2 may liquefy. In such a case, I would take a hairdryer and carefully blow hot air over the CaCl2 (outside) and when it looks reasonably dry, put it in the oven.

[Edited on 9-10-20 by woelen]

teodor - 9-10-2020 at 01:18

Drying CaCl2 is a new conception for me. I always treated any used CaCl2 as a waste, the same way as its numerous solutions.
May be I should also reconsider my bad practices.
The only concern about ether is peroxides. I had experience with such ether, even tiny drops of residue explode with great power. After that experience I test & remove peroxides before any operations which require applying heat to ethereal residue.

[Edited on 9-10-2020 by teodor]

But I have my own craziness, I still recover ZnCl2 from organic wastes, have a nice purification procedure by the way.



[Edited on 9-10-2020 by teodor]