Where to get deionized water? Is distilled water the same?

[Dennis S]

http://forums.macresource.com/read.php?1,653187

From this post about a perfumey-smelling mattress, I was advised to use deionized water, among other ingredients. I assume it acts as a chelator. Will distilled water work as well? If deionized water is what works best, where can I get it and is it expensive?

[iaJim]

If you know someone who has a saltwater aquarium, it's likely that they have a RO-DI unit that makes deionized water. Not expensive at all unless you have to buy the unit to get a gallon or two. It's likely that an aquarium store may have it as well. You'd have to ask though, it won't be out for sale.

[Racer X]

most decent grocery stores have distilled water in 1 gallon jugs.

many people use it in humidifiers and steam irons

[Dennis S]

Distilled water is no problem finding.

[freeradical]

Deionized water is expensive; it has had all mineral content removed, typically with ion exchange resins filters. It's expensive; you normally find it in chemistry labs.

The water supplied to your home has been remediated with something like sodium hydroxide to precipitate out harmful cations such as lead, mercury, uranium etc. Excessive fluoride can can be removed from water by adding calcium salts to precipitate calcium fluoride out of the water, or fluorides can be removed by adsorption to activated charcoal.

Chelating agents? These are typically used by doctors to treat patients with heavy metal poisoning.

[Filliam H. Muffman]

Distilled water supposedly has essentially zero minerals. A high quality industrial deionized water is functionally equivalent unless you are doing water analysis down in the 10 part per billion range.

The deionized water from a dispenser at the grocery store ($0.35 to $0.50 per gallon) should be good enough for 99.9% of home uses where distilled water was specified 30 years ago. Retail gallon jugs of distilled/deionized water are usually $0.75 to $1.50 if you do not have your own jug for the dispensers.

Edit: you can drink distilled or deionized water with no problem as long as you do not overdo it (like 4 or 6 gallons a day) and the source is sanitary.

[Dennis S]

I ran across this. I thought it was fascinating:

"The disadvantage of deionized water is that it is very corrosive to metal. Since it has no dissolved solids in it, water will seek equalibrium with whatever it contacts. So water with a pH of 7.0 can dissolve metal pipe. Especially yellow metals like copper and brass. It is also very aggressive to mild steel or "black" iron, and forget about glavanized pipe. Piping that resists the effects best is PVC or glass."

[ka jowct]

"Deionized" could be water processed through Deion Sanders. I would avoid it.

[freeradical]

Dennis S wrote:
I ran across this. I thought it was fascinating:

"The disadvantage of deionized water is that it is very corrosive to metal. Since it has no dissolved solids in it, water will seek equalibrium with whatever it contacts. So water with a pH of 7.0 can dissolve metal pipe. Especially yellow metals like copper and brass. It is also very aggressive to mild steel or "black" iron, and forget about glavanized pipe. Piping that resists the effects best is PVC or glass."

Sorry, but no.

What happens with water is that a small number of water molecules dissociate into hydronium and hydroxide ions. There is nothing "magical" about a ph of 7. It is simply a reflection of the fact that there are exactly the same number of hydronium ions as there are hydroxide ions in a sample of water. This is why pure water conducts electricity.

Copper does not react with water under any circumstances. Copper can only displace hydrogen from acid.

Look into something called the "activity series"...

[Raydog]

ka jowct wrote:
"Deionized" could be water processed through Deion Sanders. I would avoid it.

Now that's funny!