Types of Calcium Chloride

[easttn]

I see on pool math there are two types of Calcium Chloride. One being Dihydrate and the other I assume is Anhydrous. Ive been looking around the internet and all I see is the Dihydrate type. Unless I'm wrong. The dosage amounts seem to line up with the Dihydrate dosage on poolmath at least. I havent found anything that matches the Anhydrous version. The closest thing I have found from the dosage amounts is this: http://www.poolsupplymall.com/pool-...ce-pak-300-calcium-hardness-increaser-15-lbs/ at 1LB per 10,000 gallons to raise CH 10ppm.

Ive seen that the Dihydrate type is 77-80% Calcium Chloride and the Anhydrous type is 90+%. That doesnt make sense since Leslies Hardness Plus MSDS shows 94-97% Calcium Chloride (http://www.lesliesmsds.com/Document/21/82/7a6b21b8-8fb3-444d-805d-b5f5030f1c83.pdf) and the dosage shows Dihydrate on poolmath.

How do you know which type you are getting?
Are there any brands of Anhydrous Calcium Chloride?

 

[Abigail K]

It is difficult to find anhydrous calcium chloride since CaCl₂ is hygroscopic (i.e. it absorbs water from the environment/atmosphere).
Even if you can find the anhydrous form, once the container/packaging is opened, it is difficult to maintain CaCl₂ in the anhydrous form due to the above reason.

 

[chem geek]

The Leslie's dosage may be off some. If their product is as shown in their MSDS, then the anhydrous dosage would be correct. So one of the two is wrong -- either Leslie's MSDS or their dosage recommendation.

 

[easttn]

According to this page http://www.answers.com/topic/calcium-chloride you should be able to distinguish the types of calcium chloride from this information in the MSDS:

Anhydrous: Molar Mass: 110.98 g/mol, Density: 2.15 g/cm3, Melting Point: 772°C, Boiling Point: 1935°C
Dihydrate: Molar Mass: 147.014 g/mol, Density: 1.835 g/cm3, Melting Point: 176°C
Monohydrate: Molar Mass: 128.999 g/mol, Melting Point: 260°C
Tetrahydrate: Molar Mass: 183.045 g/mol, Density: 1.83 g/cm3, Melting Point: 45.5°C
Hexahydrate: Molar Mass: 219.08 g/mol, Density: 1.71 g/cm3, Melting Point: 30°C



If that is the case then looks like most Calcium Chloride products are Anhydrous.

Monohydrate:
Dowflake Xtra: 83-87% Calcium Chloride, Melting Point 260°C
http://www.tgrsupply.com/wp-content/uploads/2013/10/Dowflake Xtra MSDS.pdf


Dihydrate:
Downflake Calcium Chloride: 77-80% Calcium Chloride, Melting Point 174°C
https://ehs.cranesville.com/msds.pdfs/MSDS(D022).pdf


Anhydrous:
Leslies Hardness Plus: 94-97% Calcium Chloride, Melting Point 772°C
http://www.lesliesmsds.com/Document/21/82/7a6b21b8-8fb3-444d-805d-b5f5030f1c83.pdf

Peladown: 90-92% Calcium Chloride, Melting Point 772°C
http://www1.mscdirect.com/MSDS/MSDS00019/09246232-20110714.PDF

PoolTime CH Increaser: 75-97% Calcium Chloride, Melting Point 772°C
http://www.homedepot.com/catalog/pdfImages/07/071674fa-8450-4fe3-a1cd-e26ff42737fe.pdf

Vantage CH Increaser: 90-97% Calcium Chloride, Melting Point 772°C
http://www.vantagewatercare.com/MSDS - VANTAGE Calcium Hardness Increaser_086.pdf

ChemOne Calcium Chloride: 94-100% Calcium Chloride, Melting Point 772°C
http://www.chemone.com/default/msds/Calcium Chloride.pdf

SpaGuard: 75-97% Calcium Chloride, Melting Point 772°C
http://www.thepoolteamstore.com/subpages/pdfs/SpaGuard Calcium Hardness Increaser.pdf

Regal Calcium Increaser: 75-97% Calcium Chloride, Melting Point 772°C
http://www.copooldoctor.com/images/stories/pdf/Regal Calcium Increaser.PDF

AquaGuard CH Increaser: 94% Calcium Chloride, Melting Point 782°C
http://www.sfm.state.or.us/cr2k_subdb/MSDS/AQUA_GUARD_CALCIUM_HARD_INCREASER.PDF

AquaZone CH Increaser: 94-97% Calcium Chloride, Melting Point 772°C
http://www.aquachemicalsupply.com/PDFs/calciumhardnessincreaseraquazone.pdf


Is this information correct?

 

[chem geek]

Yes that looks correct. For those anhydrous that list calcium chloride with potentially low percentages of 75%, they might be impure and the large range of 75-97% makes it hard to know how to dose.

 

[easttn]

Yea thats what I was afraid of.

Will 95% Calcium Chloride put 95% Calcium in water or is it some other percentage?
Also 78% Calcium Chloride?

Example
1,000 gallons water with 95% Calcium Chloride
0.0083333333333333333 / 0.95 = 0.0087719 LBS to raise CH 1ppm per 1,000 gallons

1,000 gallons water with 78% Calcium Chloride
0.0083333333333333333 / 0.78 = 0.0106837 LBS to raise CH 1ppm per 1,000 gallons

 

[chem geek]

It puts 95% of the weight of product as calcium chloride, not calcium alone. As for Calcium Hardness (CH), it is not measured in weight units of calcium alone, but of calcium carbonate. You can convert from one to the other (though PoolMath does that for you) by multiplying weight of calcium chloride (so 95% of weight of product you add) by (100.0869 g/mole CaCO₃)) / (110.98 g/mole CaCl) = 0.9018

 

[easttn]

More complicated than I thought. Just curious as to how it worked out. Thanks Again.

 

[easttn]

For those that anhydrous that list calcium chloride with potentially low percentages of 75%, they might be impure and the large range of 75-97% makes it hard to know how to dose.

You may already know this but I noticed one of the reasons that it shows a wide percentage range is because the manufacturer will list more than one brand of product instead of just one. One of them may be 75% and the other 97% and/or somewhere in between.

 

[chem geek]

Thanks for letting me know about why there is a range sometimes. I didn't realize an MSDS could cover multiple products. I always thought it was just due to variation they allowed in manufacturing to give them flexibility.

 

[easttn]

No problem. Surprised I knew something you didnt.
I would like to post an example but I dont remember where I saw it at or even what chemical. I just remember seeing several brands where the brand name goes in the msds.

 

[easttn]

I found one.
http://www.tetrachemicals.com/getFile.asp?File_Content_ID=1196
If link doesnt work go here and click Material Data Safety Sheet
http://www.tetrachemicals.com/Products/Calcium_Chloride/Dry_Calcium_Chloride/TETRA_Flake.aqf

Calcium Chloride 74-100%
It lists a few different brands.
Tetra Flake is dihydrate (77%) and Tetra94 is anhydrous (94-97%).

 

[chem geek]

Thanks. That makes sense.

 

[Gary Davis]

I realize this is an old thread but we just came up with new related information as to what the mystery percentage is made of in typical calcium chloride packages.
Hopefully when people come here after a search, they'll benefit and maybe even correct any errors in the calculations below.

As you mentioned, there are a variety of "strengths" of calcium chloride on the market and we all are worried at first about the mystery missing percentage.
Types of Calcium Chloride

That's a great find of what that mystery ~6 percent is comprised of (actually it was a mystery 3%).

• Product name = Calcium Chloride 94% anhydrous CAS 10043-52-4
• CaCl2 purity = 94% minimum (result 95.6)
• Ca(OH)2 alkalinity = 0.25% max (result 0.13%)
• NaCl alkali chloride = 5% max (result 2.8%)
• Insoluble H2O = 0.25% max (result 0.02%)
• Fe = 0.006% max (result 0.002%)
• MgCl2 = 0.5% max (result 0.25%)
• CaSO4 = 0.5% max (result 0.03%)
• pH = 7.5 to 11.0 (result 8.8)

Nominally it's 6.5% pot luck ingredients, but in actuality, according to the numbers you unearthed, it's 3% mystery ingredients, mostly table salt.

• Nominal: 0.25% + 5% + 0.25% + 0.006 + %0.5% + 0.5% = 6.506% (with sig figs, that's 6%, most of which is table salt)
• Result: 0.13% + 2.8% + 0.02% + 0.002 + %0.25% + 0.03% =3.232% (with sig figs, that's 3%, most of which is table salt)

As for dosing calculations the percentage is multiplied by about 90% (where that 0.9018 is taken care of automatically in pool math) as Richard Falk explained.

• 25 pounds of 94% by weight of calcium chloride x 100.0869 g/mole CaCO3 / 110.98 g/mole CaCl = 21.2 pounds effective calcium (is that math correct?)
  • 25 pounds of 97% by weight of calcium chloride x 100.0869 g/mole CaCO3 / 110.98 g/mole CaCl = 21.9 pounds effective calcium (is that math correct?)
• 25 pounds of 100% by weight of calcium chloride x 100.0869 g/mole CaCO3 / 110.98 g/mole CaCl = 22.6 pounds effective calcium (is that math correct?)

I bought mine in the summer for about a dollar a pound for the 94% calcium chloride shipped to my door.
There's always the discussion of what type of calcium chloride it is though.

calcium chloride vs calcium chloride dihydrate​

For about two dollars a pound for that Puritech 100% calcium chloride it's twice as expensive, but it doesn't have the 3% to 6% mystery ingredients my shipment had (which appears to be mostly table salt with a pinch of magnesium chloride).

I must admit though that I've always been confused by calcium chloride concentrations because I don't have the Richard Falk math figured out for calcium chloride yet. If you have the math figured out such that we can compare the effective dosage in our head like we can for chlorine, please let me know!

Calcium Chloride Concentrations​

"Commercial dry Calcium Chloride Concentrations are 74%, 77% (dihydrate), 83-85%, 88-90%, and 94-96% (anhydrous)."