Sciencemadness Discussion Board

OTC Calcium Chloride - Good for Drying

subsecret - 4-1-2015 at 15:21

I found this at my local hardware store, in the pool section: HTH Calcium Plus. The entire container cost me about $7. I heated about 5 grams of it in a crucible until most of it had melted, and figured out that the mass had not changed much. The MSDS says that it contains several percent water, so heating it in an oven would be a good idea before use. The MSDS lists it as 90-95% CaCl2, and it comes in the form of small prills, about 1-2 mm in diameter.



0007318761313_500X500.jpg - 25kB

Texium - 4-1-2015 at 15:25

I've found that anhydrous calcium chloride can also be purchased at the hardware store in the cleaning supplies area, used for drying out damp areas. I can't remember the brand name, but the stuff I found was in a sealed blue plastic bag. It's in the form of nice white prills that look quite pure.

aga - 4-1-2015 at 15:27

Slap it onto a hotplate. Heat it a lot.

It will end up as a white cake that you have to scrape off of the plate.

Not exactly anhydrous, but damned close.

subsecret - 4-1-2015 at 15:58

@zts16: I believe that it's sold as Damp-Rid. I've seen paper cartons and plastic cups of this stuff.

Bert - 4-1-2015 at 16:10

Quote: Originally posted by aga  
Slap it onto a hotplate. Heat it a lot.

It will end up as a white cake that you have to scrape off of the plate.

Not exactly anhydrous, but damned close.


Or microwave it in a casserole-

macckone - 4-1-2015 at 17:54

If you live in a cold climate, Qik Joe Ice Melt is basically calcium chloride with a few other chlorides as contaminants. Specifically, sodium chloride, potassium chloride and strontium chloride.

CaptainPike - 6-1-2015 at 14:00

I have baked the cheap stuff that comes in the huge bag from Walmart (or at every convenience store, these days) in the kitchen oven, along with other desiccants such as magnesium sulfate and a copper salt used to kill roots. The latter being especially handy when appropriate, since it will turn a nice blue when it encounters water – just like sending a probe down below the cloudy atmosphere of a hostile planet and receiving it back data from the invisible depths below.

With the calcium chloride, I didn't see much physical change in the prills, or beads really, even after having been subjected to 525°F for at least a half an hour. Whereas the sulfates mentioned both powdered up, with the cupric one additionally losing almost all of its brilliant blue hue.

aga - 6-1-2015 at 15:23

Quote: Originally posted by Bert  
Or microwave it in a casserole-

I get the feeling that you need introducing to Jamie Oliver.

http://www.jamieoliver.com/recipes/beef-recipes/jools-s-favo...

aga - 6-1-2015 at 15:39

Quote: Originally posted by CaptainPike  
With the calcium chloride, I didn't see much physical change in the prills, or beads really

I saw a couple of organic solvents go from cloudy to clear after adding anhydrous CaCl2, hopefully meaning that the remaining water was sequestrated.

No change seen in the calcium chloride though, unless there's a LOT of water, in which case it turns to slush.

dermolotov - 7-1-2015 at 10:43

Yupp. This is what I recommend in lue of impure Magnesium Sulphate and others.

This I have found to interfere much less and dissolve completely in water with no insolubles. I just bake for 30 minutes on 425 on my $5 toaster oven. As mentioned, bit becomes a hard cake that I scrape off and into a powder.

I get it from Wal-Mart :D

BobD1001 - 7-1-2015 at 14:22

Here in Pennsylvania during the winter months you can find huge amount of pure calcium chloride (used to melt ice on walkways) for dirt cheap. A couple hours before reading this post I bought a 50lb resealable bucket of pure calcium chloride (marketed as pure, I'm sure there are some impurities and water content) for $19.99 at BJ's wholesale since we just had our first snowstorm. I will also use it as a desiccant when I dont want to use my molecular sieves.