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FeedMe94
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Distilled vs Deionized Water
On every synthesis i made before i had to remove the acidity of the final product by run distilled water through the product and then distilled water
+ sodium bicarbonate solution. I just find out that the water i was using was deionized and not distilled. What is the differences and what affect
will have on my final product?
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anewsoul
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Basically DI water is made by running water through special columns that exchange mineral ions in the water for hydroxide and hydronium ions to make
pure water. Distilled water is made, as you probably know, by distilling the water so that only pure water comes over and leaves behind minerals. DI
water is used in labs because the process of making it is way more energy efficient. In either case, what you have is essentially pure mineral free
water, so it doesn't matter which one is used.
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BromicAcid
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Deionized can have residual organic contamination, deioinziation is usually accompanied by UV treatment and ozonlysis to ensure purity.
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Fulmen
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Only when needed. In many applications plain DI is more than adequate.
We're not banging rocks together here. We know how to put a man back together.
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FeedMe94
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Thanks for the answers. Only DI water is available here
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CouchHatter
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Previously, I was under the impression that, when it came to distilled vs. DI, distilled water was more pure. So pure, being near or at 0 ppm, it
would bind with the minerals in your body, depleting them, and therefore is unsafe to drink... At 50 ppm, water ought to be plenty safe to drink,
right?
However, yesterday in my college gen chem lab course, my lab manager told us the opposite. Furthermore, we were provided with this table. When I asked
if price was why we were using DI instead of distilled (to add back volume to a boiled water sample) he said that, no, it was because the DI was more
pure. This is against everything I thought I learned about water purity, although it is reflected in the table.
Is the table accurate? Where would the 50ppm in distilled water come from? Wouldn't the act of distillation remove 100% of impurities except
volatiles? (not solids, so doesn't count towards the TDS ppm) Just can't figure out another way that impurities could make it through a distillation.
Are there exceptions for certain molecules?
On ResearchGate, someone said of double distillation, | Quote: | | "The problem with it is that since it is continuous distillation, some contaminants will come across with the water." |
But what contaminants would do this, and how? Ride the vapor up to the condenser?
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macckone
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Distilled water will have contaminants of the distillation equipment material.
This could be glass, copper, stainless steel or PTFE, or possibly other compounds with solder (tin, lead, silver).
As well as volatiles.
Deionized and reverse osmosis water will have organic matrix contaminants, which are usually non-volatile.
Conductivity measurement will not properly detect organic contaminants.
So water with organic contaminants will not conduct where the same level of copper or silica for example would.
Distillation can aerosolize contaminants.
While bead bed DI water can allow all manner of contaminants through.
filter type DI membranes generally remove more contaminants but are usually used for finishing as they are more expensive and generally cannot be
regenerated.
RO filters vary a lot in efficiency and come in a range of removal levels, from why am I paying for this to damn I wanted that last sodium atom. Some
actually contain a deionization resin to lengthen the life and improve the final product.
Reverse osmosis finishing filters are not the same as regular reverse osmosis filters sold for home use which are usually one stage.
In the semiconductor industry, water is distilled, deionized then put through a reverse osmosis filter for finishing.
After use the water is recycled as it is significantly more pure than tap water.
But that is the ultimate special case as a single contaminating atom of any kind can ruin a transistor and hence render a chip useless.
For the chemistry most of us are doing, anything significantly more pure than tap water is going to be fine.
ie. store bought distilled water, which may actually be bed deionized, filtered, and ozonated, check the label.
And on a final note, most water will deplete your body of minerals unless you have extremely hard water.
But, we get most of our minerals from food, so it isn't the concern people make it out to be.
Standard tap water is generally about 350 ppm according to google with 500ppm being the limit according to the epa.
Compared to blood salinity of 0.9% or 9000 ppm.
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Tsjerk
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In microbiology MilliQ water is the standard, which is deionized water, and has a resistance of around 1 μS/cm. Every lab has it's own columns.
Edit: the fusion of West and East Germany brought up some perculities, where mostly scientist from the East couldn't culture their strains when they
came to the West. Adding trace minerals usually was the solution, the strains from the East were selected on basically tap water, and sometimes
needed just a pinch of something.
[Edited on 15-10-2021 by Tsjerk]
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unionised
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Reverse osmosis is generally use as the starting, not the finishing, part of the purification process.
It will convert drinking water to so called "Type 3" water which is good enough for washing up, but that's about it.
Further purification is then done by deionisation (typically mixed resin beds) or electrodialysis.
Occasionally, distillation is still used- with all quartz apparatus. The problem is that when you boil water you get tiny droplets formed when the
bubbles burst and that spray gets carried over into the product.
So stills are often used in pairs where one feeds the other.
That's the origin of "double distilled" water.
https://www.elgalabwater.com/blog/different-types-pure-water...
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Morgan
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As an aside on distilled water and trace elements, I've wondered about distilled vinegar. Reading about the acidity of tomato sauce cooked for longer
periods in stainless steel pots, some nickel and chromium can be detected.
Or say you occasionally clean you pot with Barkeeper's friend (oxalic acid) and create a "fresh surface" over and over.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4284091/
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woelen
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For home chemistry purposes in practice I never noticed any differences. My experiments worked equally well with all brands of distilled and deionized
water I have used over the years. Nowadays I just use the cheapest I can get.
Using tap water, however, does make a difference. In NL we have quite good tap water, but still, with certain experiments this gives problems (e.g.
with silver salts and lead salts you always get cloudy solutions, with alkaline vanadate(IV) you always get brown precipitates, etc.).
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woelen
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Thread Moved
16-10-2021 at 03:44 |
woelen
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I moved the thread from the energetic materials section to general chemistry. This has nothing to do with energetics.
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Tsjerk
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I think that for most cases that ask for dH2O (distilled or deionized) you can use water purified with standard tapwater demineralizing columns. The
things they sell to de-harden drinking water. Here I can buy two cartridges for 5 euro which will problably last a lifetime when only used for lab
purposes.
You could run the water through them a couple of times just to be sure. These cartridges contain the standard resin which replaces positive and
negative ions with H+ and OH-.
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S.C. Wack
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Nonsense, bullshit, stupidity, etc. of some sort.
Quote: Originally posted by unionised  | | The problem is that when you boil water you get tiny droplets formed when the bubbles burst and that spray gets carried over into the product.
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There are of course spray/bump/steam traps, which Laboy had a selection of last time I went through their site.
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Tsjerk
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You can even regenerate the resin when you manage to separate the two kinds. They have a different density, when I tried I couldn't get one to float
while the other didn't, but I haven't tried in anything else than water, if both sink you could add salt until one floats, or when they both float you
can add an alcohol.
After adding salt you definitely need to regenerate with acid and base, afterwards you can use the different resins as a catalyst in organic
reactions, which seems to work pretty well.
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macckone
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Unionized,
Your link generates a page not found.
All of the glass water distillation rigs i have seen are borosilicate. I have a quartz glass rig, but i only use it for high boiling point stuff.
Distillation equipment in labs also comes in stainless steel. The stainless is mainly used in medical labs, we had a few at utmb galveston but they
may have been retired. The nice thing about distillation is it guarantees the water is sterile but not necessarily free from other things. Copper is
mostly used for alcohol of the drinking variety. Ptfe is exotic but it exists. I think the ptfe distillation is mainly used in industry and not for
water.
Reverse osmosis finishing filters are not the same as the type you are used to produce drinking water. They are much tighter tolerances. And would
be destroyed by tap water.
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unionised
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Does this link work?
https://www.elgalabwater.com/blog/different-types-pure-water...
Here's a vid of a quartz still.
https://www.youtube.com/watch?v=gulqhdTXnX0
You can separate the mixed bed resins by putting them in saturated salt solution. One resin floats, the other doesn't.
Sub distilled solvents avoid the spray problem altogether and achieve much higher purity.
If you are doing the sort of work that requires this degree of purity, you also need a clean-room
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macckone
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+1 on clean room
A chip foundry water needs to be more pure than type 1 in the link.
I find it interesting they reference D1193 rather than D5127.
I don't think any of us need acs ultratrace water for our home lab.
A side note for D5127 compliance you cannot expose the water to the atmosphere either. Gas absorption = bad.
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zed
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I hail from an area known for the crappy-dirty taste of its tap-water.
Even though it was long ago, one of my buddies had a pretty good purification system.
First ultra-filtration, through a hard carbon filter... then reverse osmosis, and finally distillation. During the course of the distillation, the
fore-run is discarded.
Seemed like a lot of trouble just to clean-up water. At the time I preferred beer anyway.
And the resultant water? Utterly delicious!
For science, such water may be overkill. At my UNI, the water produced by our deionization system, seemed to work for most purposes,
but the Profs were pretty surprised when the water was tested via pH Meter.
It consistently showed pH of 5.
I mean, would you really want to be drinking that, without knowing more?
[Edited on 20-10-2021 by zed]
[Edited on 20-10-2021 by zed]
[Edited on 20-10-2021 by zed]
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Metacelsus
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The pH of 5 is easily explained by atmospheric CO2 dissolving in it and forming carbonic acid. Without minerals there's nothing to buffer it.
[Edited on 2021-10-20 by Metacelsus]
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Tsjerk
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Many pH electrodes don't like measuring pH when there is absolutely no salt present. I'm sure the pH would go to 7 when you add a pinch of salt.
CO2 forms carbonic acid with water, which would be taken up as carbonate by the resin.
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pneumatician
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| Quote: Originally posted by CouchHatter | Previously, I was under the impression that, when it came to distilled vs. DI, distilled water was more pure. So pure, being near or at 0 ppm, it
would bind with the minerals in your body, depleting them, and therefore is unsafe to drink... At 50 ppm, water ought to be plenty safe to drink,
right?
However, yesterday in my college gen chem lab course, my lab manager told us the opposite. Furthermore, we were provided with this table. When I asked
if price was why we were using DI instead of distilled (to add back volume to a boiled water sample) he said that, no, it was because the DI was more
pure. This is against everything I thought I learned about water purity, although it is reflected in the table.
Is the table accurate? Where would the 50ppm in distilled water come from? Wouldn't the act of distillation remove 100% of impurities except
volatiles? (not solids, so doesn't count towards the TDS ppm) Just can't figure out another way that impurities could make it through a distillation.
Are there exceptions for certain molecules?
On ResearchGate, someone said of double distillation, | Quote: | | "The problem with it is that since it is continuous distillation, some contaminants will come across with the water." |
But what contaminants would do this, and how? Ride the vapor up to the condenser? |
I drink lots of distilled and, no, the distilled water only remove your body waste. How DW enter cells "get" or dissolve "minerals" DNA and remove
from your body??? This is like if you enter in a bath tube and your body is DISSOLVED!!! :-) OF COURSE NOT!!!
And in reverse mode! Many times in summer I float around 30-45 minutes in the sea and my body is not OVERSATURATED WITH MINERALS!!! or I end like a
dried sausage!! :-)) common sense my friend, common sense!!
Floating around a book: A study of prolonged fasting" where some guys put 30+ days drinking only DW & 0 food and no problem!!!
I read this book many years after I ended in this reasoning, and I said, oh, good :-)
Maybe learn how to distillate water??? not all is in the books, no???
common sense??
Put 8 liters of tap water in a 10 flask. Distil the first 500ml in a measuring cylinder & and pull them down the sewer, now continue in a 5 liters
jug. When the jug is full stop the distillation. Now you have 5 liters of pure water. Discard the water full of shit in the 10 liters flask. To clean
the 10 liter flask I need to put some HCL...
If you want it more pure insert a Kjeldahl and put the minimum temp for a slow distillation...
If you want more pure, repeat, this is called bi-distilled water :-)
Shit ride the vapor and go up if the temp is too much, bubbles & microexplosions too carry shit up the condenser.
In the first 0.5-3 liters of distillation a lot of big FFFFUUUSSSSSSSS! it happens and the jug is filled with hot vapor passing all my 60 cm
condenser... a day a 5l jug cracked with the temp subite change... No, the temp is not more than the needed to water boil point...
if you stop a water distillation when around 30% is done you can see this floating... from tap water... but every season, month... the quantity of
shit in water is different.
And well, a lot more I can say about water but enought for the wise... :-)
[Edited on 22-11-2021 by pneumatician]
[Edited on 22-11-2021 by pneumatician]
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pneumatician
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| Quote: Originally posted by macckone |
And on a final note, most water will deplete your body of minerals unless you have extremely hard water.
But, we get most of our minerals from food, so it isn't the concern people make it out to be.
Standard tap water is generally about 350 ppm according to google with 500ppm being the limit according to the epa.
Compared to blood salinity of 0.9% or 9000 ppm.
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too much "minerals" in water and your intracells water-jelly is full of shit where pathogens can live happy!
from food you get little minerals, earth is overexploited and only replenished with nitrates :-)
"standard tap water" is proof of the limited brain of some
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macckone
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Pneumatician,
Your lack of information about farming is quite surprising.
Most farmers are now taught about micro nutrients and a standard soil amendment is 'granite dust'.
Even industrial farms add micronutrient solutions, which are basically engineered for a particular crop.
The minerals humans need like chromium and selenium that are viewed as 'bad' are necessary for humans.
Some plants need them as well. Eating a varied diet reduces the need for supplementation.
Salt water fish literally get mineral rich water their whole lives.
Drinking nothing but water and not eating is NOT GOOD for the body.
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neptunium
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The ppm value for measuring quality of water are quite useless, Pure de ionized water should have a conductivity of 0.055uS/cm2 or a resistance above
18Mohm.
This should still show a few ppb of mostly chlorides and sulfates if starting from tap water. In a previous video, I found quite a few ppm of nitrates
and chlorides from store bought distilled water. I now use a reverse osmosis set up followed by a nuclear grade cations and anions exchange resin
which gives me pretty damn pure water for all my analysis.
In the nuclear industry, where we need large amount of pretty clean water (although not as clean as semi conductors manufacturer )
he city water filtered through sand, activated carbon and softner first, then passed through a double Reverse Osmosis rig, and finally ion exchange
resin. This yield water with low ppb organics, sub ppb (<0.1ppb) chlorides, sulfates etc.. and sub ppb of sodium and calcium . Most metals detected
in the ppt range or lower, come from later contamination, mostly iron, copper, manganese and nickel.
[Edited on 22-11-2021 by neptunium]
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