Evaporated Sea-Salt--cheap

[wooden_reefer]

I am talking about the kind for water softener. Some salt for water softener is rock salt, NaCl. I am not talking about this kind either.

The kind I am interested in comes from evaporation of sea water, $5 for 50 lbs, but it also is labeled as "pure".

Does the process of drying sea water and crystalization purify the salt as NaCl?

I don't know how it works. If indeed the process purifies the NaCl and removes other salts (such as calcium and potassium and magnesium), what is the process of separation?

If indeed the salt is really sea salt, it means that this salt may be good enough for crude non-reef applications. It might even be good enough for fish. at least it can be used during cycling so that 100% water change after cycling would cost little.

What is it? Is it pure NaCl or real sea salt?

 

[KarlBob]

I seriously doubt that anyone would go to the trouble of removing all the other salts from evaporated seawater. On the other hand, I don't know how people would react to arsenic salts, lead chloride, etc. in their water softener salt.

 

[wooden_reefer]

Those who know physics (material science) please tell me if crystalization is a separation process. That is , only NaCl will cling to NaCl crystal.

I vaguely remember may be this is possible, but I have given all back to the professor.

Even if crystalization is a separation process, the question still is whether other salts will also crystalize and separate from other salts, and at the end how would each salt be separated. Do the different crystals have different density so the various crystals can be separated.

It is $5 for 50 pounds. How can any involved process be so cheap?

 

[wooden_reefer]

I think I may have the answer.

Other salts may not form crystals at the same condition.

Evaporated may not mean it is all dried up. Crystals of NaCl may be formed when not all the water is gone. At this stage, large blocks of NaCl crystal may be collected from saturated solutions of other salts still in solution.

I really like to know. May be I will try a damsel on this stuff.

 

[wooden_reefer]

Only potassium and sodium ions can be used to recharge the resin.

It cannot say pure if it contains ineffective salts of calcium and magnesium. This would be misinformation.

 

[KarlBob]

I would think it could say pure if it was made from "pure" evaporated seawater.

If they evaporate the water all the way to dryness they will have salts of sodium, potassium, calcium, magnesium, lead, copper, and everything else.

I don't know whether they dry it all the way, or just gather the crystals that form first. My guess is that the major salts like sodium and potassium chloride would be the first ones to reach saturation, and therefore the first ones to precipitate. The lower the initial concentration, the later a salt would precipitate. Note: I could be totally wrong on this, I don't know whether multiple solutes reach saturation and precipitate together or separately.

 

[ctenophors rule]

it may be sea salt, but when it evaporates certain elements, molecules, and compounds become ireversably joined.

they are no longer soluable in water, and as such is not safe for aquarium use.

salt should be one of the last things you try and cut corners on, i have been reading marine chemistry br cr brightwell, and it is a great read, realy explains things in an easy to understand way, and he talks about this in lenght giving examples.

 

[wooden_reefer]

<a href=showthread.php?s=&postid=15245063#post15245063 target=_blank>Originally posted</a> by ctenophors rule
it may be sea salt, but when it evaporates certain elements, molecules, and compounds become ireversably joined.

they are no longer soluable in water, and as such is not safe for aquarium use.

salt should be one of the last things you try and cut corners on, i have been reading marine chemistry br cr brightwell, and it is a great read, realy explains things in an easy to understand way, and he talks about this in lenght giving examples.

I think no new ions is formed when the seawater dries. Different combinations of salt emerge some, CaCO3 and MgCO3, does not dissolve easily.

I have tried redisolving salt crusts. Most dissolves with just a white film on the bottom.

I won't use it in a reef tank, may be for cycling and 100% water change later.

May be good for fish only after chemical filtration.