Sciencemadness Discussion Board - Destilling HCl - the lowest lowtech you can go

Destilling HCl - the lowest lowtech you can go

Diachrynic - 28-3-2018 at 07:04

Exited about my first liter of hardware store HCl I was surprised it was dyed green/yellow.

Since hydrochloric acid if pure is colorless, I want to distill it.

Now comes the challenge: I don't have a distillation setup and I won't have one anytime soon.

So, what is the lowest lowtech you can go?

I looked up plastic acid resistance charts, but even if PVC and PET can withstand acid at room temp, I don't think it would be pleased by boiling water, let alone hydrochloric acid.

I know that distillation of HCl will not concentrate it beyond 20% but I am fine with that, I just need to get all the dyes and contaminants out of there.

I also know that heating a mix of sodium bisulfate and sodium chloride generated pretty pure HCl, but then again I wonder how to do that without distillation setup.

Any ideas beyond "Get glassware or give up"?

Plunkett - 28-3-2018 at 07:21

This method might interest you; all you need is three plastic containers and time. https://youtu.be/jv1Ms6Subg4

Ubya - 28-3-2018 at 07:27

Quote:

I also know that heating a mix of sodium bisulfate and sodium chloride generated pretty pure HCl, but then again I wonder how to do that without distillation setup.

if i remember correctly this reaction also works without dissolving the reagents in water, you can just mix the dry powders toghether and heat the mixture to get HCl gas, which can be easily dissolved in water to get concentrated HCl acid. no distillation equipment needed

[Edited on 28-3-2018 by Ubya]

Sulaiman - 28-3-2018 at 08:16

This document details an industrial approach
Attachment: E259.pdf (72kB)
This file has been downloaded 352 times

To me the key part is that the reason for cleaning the acid is to make it cosmetically attractive to customers,
i.e. the yellow is not a chemistry problem but an aesthetic problem.
If your experiments can tolerate a few ppm iron and/or chlorine (most can) then just use as-is.

I might try some activated charcoal or even powdered common wood charcoal, it works on many colorants.

If on a budget (aren't we all) then I think that a (£15) kit like this would be adequate for hydrochloric acid and most amateur distillation uses.
https://www.ebay.co.uk/itm/250ml-14-23-Glass-Distillation-Ap...
I went for a more expensive kit and have no regrets, similar to this
https://www.ebay.co.uk/itm/500ml-24-40-Glass-Distillation-Ap...

I'm not sure but I think that if you are going to distil the acid:

if you distil the concentrated acid,
the concentration in the boiling pot will tend towards the 20.2% azeotrope,
so the first thing to evaporate will be very concentrated acid
(this is why the slow method above works)

it may be better to dilute the acid to Az. before distilling ?

[Edited on 28-3-2018 by Sulaiman]

RogueRose - 28-3-2018 at 09:25

Well I recently tried to heat about 15% HCl in a PET bottle in the microwave with the cap on tightly. it was a 1/2 gallon bottle and I had about 90% full. I only needed to warm it from room temp up to about 120-130, so I used about 30 second bursts on 70% power.

The first cycle went well and I noticed a slight increase in them. I next did 30 sec at 100% and the bottle wobbled when a dent in it had been pushed out from inner pressure. I squeezed the bottle and it wasn't even 90F yet and it had no pressure, so how did the "squeeze dent" pop out.

Repeated a few more times and then the bottle changed form and straightened out a side that had crimps and an inner curve (like coke bottle) so that it had a flat side not sloping inward then outward like a classic Coke bottle. It now looked like every other standard 2L bottle with no distinct shape and was only about 110F.

I have no idea how it managed to change the shape of the bottle, maybe HCl gas passing through the PET (though I didn't smell any). I'm still trying to figure this out as I've stored 32% HCl in PET for at least a year in a cheap soda bottle and it seemed fine, never had a problem but I'm thinking that HDPE is the way to go if handling HCl (if glass or quartz isn't available).

AJKOER - 28-3-2018 at 09:30

Lowest tech:

HCl (aq) --> Cl2 (g)

Cl2 + H2O = HCl + HOCl

2 HOCl --CuO--> 2 HCl + O2

3 HOCl --CuO--> 2 HCl + HClO3

Source: "Enhanced Bromate Formation during Chlorination of Bromide Containing Waters in the Presence of CuO: Catalytic Disproportionation of Hypobromous Acid" by Chao Liu, Urs von Gunten, and Jean-Philippe Croue, Equations (9) and (10), available at https://infoscience.epfl.ch/record/182097/files/es3021793.pd... .

Sulaiman - 28-3-2018 at 09:33

A dry PET bottle will get hot in a microwave oven.

WHY WOULD YOU MICROWAVE ANYTHING IN A SEALED CONTAINER ?
- THAT IS ASKING FOR TROUBLE

Sigmatropic - 28-3-2018 at 09:38

Ah the proton spontaneously transmutates into a chlorine atom. Now this does not work in practice nor does it on paper. Oh and if your handling chlorine you might as well handle hydrogen chloride.
Last time I checked (in practice that is, by DOING) CuO dissolves to form CuCl2.

RogueRose - 28-3-2018 at 10:27

Quote: Originally posted by Sulaiman

A dry PET bottle will get hot in a microwave oven.

WHY WOULD YOU MICROWAVE ANYTHING IN A SEALED CONTAINER ?
- THAT IS ASKING FOR TROUBLE

b/c it was room temp (liquid), about 90% of a 1/2 gallon in liquid, and doing 30 second bursts at 70% power and the bottle was (scrunched/sucked in like a vacuum) to start so there was room for expansion. I was standing watching it while it heated, not left unattended. It's not a problem.

AJKOER - 28-3-2018 at 11:12

Quote: Originally posted by Sigmatropic

Ah the proton spontaneously transmutates into a chlorine atom. Now this does not work in practice nor does it on paper. Oh and if your handling chlorine you might as well handle hydrogen chloride.
Last time I checked (in practice that is, by DOING) CuO dissolves to form CuCl2.

More details apparently needed.

First, react HCl with either MnO2, or HCl and a hypochlorire with added NaCl as thus:

2 H+ + Cl- + OCl- --> H2O + Cl2 (g)

Now, with respect to the action of CuO on HOCl, the reaction at RT is slow forming an unstable cupric hypochlorite which decomposes on standing into an insoluble cupric oxychloride.

The initial reaction of RT dilute HCl (from the action of chlorine and water) on a solid mass of CuO is slow and increases as pH is lowered creating CuCl2.

The initial action of CuO on HOCl is fast liberating mostly O2 with HCl, and secondly, 2 HCl with HClO3. The chlorate can be removed by adding KCl and freezing out KClO3. Wikipedia only cites the first reaction to quote:

"The presence of light or transition metal oxides of copper, nickel, or cobalt accelerates the exothermic decomposition into hydrochloric acid and oxygen:[10] "

Link: https://en.wikipedia.org/wiki/Hypochlorous_acid

If you do not like the copper path, use sunlight which is slower. With respect to 'doing', here is a SM reference on my reported observation with light reflected off of snow at http://www.sciencemadness.org/talk/viewthread.php?tid=17638&... , where I also noted that:

HOCl --uv--> HCl + O

has been reported to proceed more rapidly in the presence of Tartaric or Citric acid.
------------------------------------------

Here is a path to chlorine via Al, Cu, weak HOCl acid (from say H2CO3 + CaCl2 + NaOCl) from a prior thread (part of 'doing'):

Quote: Originally posted by AJKOER

To quote Wikipedia on MnO2 (link: http://en.m.wikipedia.org/wiki/MnO2 ):

"The reaction of hydrogen chloride with MnO2 was used by Carl Wilhelm Scheele in the original isolation of chlorine gas in 1774"

MnO2(s) + 4HCl(aq) → Cl2(g) + MnCl2(aq) + 2H2O(l)

New dry cell batteries could be a source for MnO2, but usually with a strong base like KOH so carefully wash the MnO2.

With respect to a source for HCl, if you cannot buy cheap iron contaminated Muriatic acid, react NaCl with battery acid (H2SO4), or with a spa pH control chemical like NaHSO4, or buy a strong organic acid like Oxalic acid.

[Edit] If you have found a source for NaOCl, but wish to avoid storing strong acids around children and others, add to the NaOCl vinegar, copper metal, aluminum foil and some sea salt. This is the making of a so called bleach battery that I have discussed previously on SM. Here is an extract:

Quote: Originally posted by AJKOER

Actually, here is a more useful way (actually, it makes the so-called bleach battery that you can use to produce electricity as well) to make some Chlorine. Steps:

1. Mix bleach (NaOCl) and vinegar (which contains Acetic acid HAc) in the volume ratio 1.4 parts of 5% vinegar to one part of 8.25% extra strength chlorine bleach.

2. Add a piece of copper metal which will function as the cathode.

3. Add an Aluminum source to act as the anode (finely cut up Al foil, for example, will also work).

4. Add a touch of sea salt (better than NaCl) to act as the electrolyte to get things started.

My take on the chemistry:

The creation of Hypochlorous acid:

NaOCl + HAc --> HOCl + NaAC

And, on the major electrochemical reactions:

H2O <--> H3O + OH-

At anode: Al + 3OH- ⇒ Al(OH)3 + 3e-

At the cathode (copper):

3 HOCl + 3 H3O+ + 3 e- ⇒ 3/2 Cl2(g) + 3 H2O

for an implied net reaction of:

3 HOCl + Al --> Al(OH)3 (s) + 3/2 Cl2 (g) Eo net = 3.93 V

This battery cell is theoretically capable of generating 3.93 volts.

Reference: see http://www.exo.net/~pauld/saltwater/ and http://sci-toys.com/scitoys/scitoys/echem/batteries/batterie... and also http://www.dtic.mil/dtic/tr/fulltext/u2/d019917.pdf

There are also many side reactions. For safety, however, it should be noted that in addition to the toxic/corrosive Chlorine gas, in the case of the use of an excess of Aluminum, some explosive hydrogen gas can also be formed (in about a day) as the protective Al2O3 coating is attacked in a salt solution permitting the reaction:

2 Al + 6 H2O --> 2 Al(OH)3 + 3 H2 (g)

[Edited on 28-8-2013 by AJKOER]

I have more recently discovered that burning Aluminum foil in a perturbed flame (just knock the burner on your stove, once lit, slightly off center, and a loud hotter flame is formed) till the Al is glowing red results in a form of weakened gamma Al2O3 covering the Aluminum that is functionally more reactive. In the context of the current galvanic cell, after modest warming, the generation of Cl2 and the dissolution of the Aluminum commences. I would also recommend a different path to HOCl as the presence of acetate in the cell after a few days apparently produces a nasty chloro-acetate. Here is my new recommendation:

Mix NaClO with CaCl2, producing an equilibrium reaction:

CaCl2 + 2 NaClO = Ca(ClO)2 + 2 NaCl

which when shaken in a large vessel containing CO2 (from say, the action of NaHCO3 on vinegar, and the solution drained carefully leaving just the heavy CO gas), a bright white precipitate of CaCO3 is formed along with Hypochlorous acid, moving the above reaction to the right:

Ca(ClO)2 + CO2 + H2O ---> CaCO3(s) + 2 HOCl

On cooling, the CaCO3 suspension collapses to a solid precipitate allowing the easy collection of the Hypochlorous acid.

[Edited on 21-9-2014 by AJKOER]

link: http://www.sciencemadness.org/talk/viewthread.php?tid=33247

[Edited on 28-3-2018 by AJKOER]

Sulaiman - 28-3-2018 at 11:19

AJKOER, I love your 'blue sky' thinking - at the very least, radical

[Edited on 28-3-2018 by Sulaiman]

aga - 28-3-2018 at 11:28

I get it now. AJKOER is in fact Kai, last of the Brunnen-G.

Obvious if you sing these 'words' :

HO Cl.

HOCl, HO C C Cl

HO H Ra, jar, um, of BrC

to this 'song' :

https://youtu.be/wYoq6sovr8Y?t=7

AJKOER - 28-3-2018 at 12:01

Aga:

You are missing the exciting part!

Per the supplied reference, CuO provides an improved disproportionation of HOCl to HClO3, like 27% of total HOCl at pH 7.6. Now, one can drip NaOCl into the reaction mix of HOCl/CuO, which will combine with the newly liberated HCl per either of the two decomposition path:

2 HOCl --CuO--> 2 HCl + O2

3 HOCl --CuO--> 2 HCl + HClO3

thereby maintaining pH, while creating yet even more HOCl (for total chlorate formation) via:

OCl- + HCl --> Cl- + HOCl

Also, consider the reversal of the radical equation, where the reverse reaction is likely significant in so called alkaline bleaching with oxygen (which can be driven by transition metals), or the sensitivity of alkaline chlorine bleaches to air/dust particle exposure leading to decomposition:

.O2- + .OH = O2 + OH- (Eq 5.98 at https://books.google.com/books?id=57noBQAAQBAJ&pg=PT715&... )

As both the superoxide radical anion and the hydroxyl radical can contribute also to chlorate formation, shaking the reaction chamber, capturing oxygen which I would mix with air, may further increase chlorate yield!!
------------------------------------------------------------------------

Note, my prior chlorate via photolysis thread detailed an approach which resulted in much less than 27%.

[Edited on 29-3-2018 by AJKOER]

Texium - 28-3-2018 at 14:19

Quote: Originally posted by AJKOER

You are missing the exciting part!

Oh yes, it's ALL so exciting when you become divorced from reality, and all of your "research" is actually just misconstruing journal articles that you don't really understand and cobbling it together vaguely with articles from Wikipedia and Atomistry.

Diachrynic - 28-3-2018 at 15:43

Thank you all for your replies! I'll take a look what would be the best solution for me.

I really like the idea of the boxes! I'll try that out.

And I will think about a glass setup, but right now this will remain a dream.

AJKOER - 28-3-2018 at 15:54

Quote: Originally posted by Texium (zts16)

Quote: Originally posted by AJKOER

You are missing the exciting part!

For your education, Atomistry is an extract from historical major science journals (mostly chemical journals of UK and US) for which the original copyright has since expired. The material compiled is then copyrighted anew. Yes, some of the science theory is dated, but reports as to properties and paths for preparation of compounds are fairly good in my opinion.

Now yes, Wikipedia is not uniform in quality, but did you know that if something is wrong, you can edit the material and if other pundits agree with your content, it will replace the poor content. So, if something is off in Wikipedia and you know better, one could argue that it is the reader's fault that the quality is not there!
-------------------------------------------------------------------------

Really, my comments are generally misconstrued?

Surprising to me as to how my chlorate threads (assuming I could possibly understand any of the theory even with links provided to sources) and, especially all those, pictures, pictures, pictures..., indicating an unlikely confirmation of some of my misconstruing?

Here is a sample link: http://www.sciencemadness.org/talk/viewthread.php?tid=34429#... .

By the way, could you provide an example of something, you feel I misconstrued? I do omit as to being weak in certain fields, so I may actually agree with you.

Here again is the journal reference to the reputed action of CuO on HOCl (and also on HOBr): Source: "Enhanced Bromate Formation during Chlorination of Bromide Containing Waters in the Presence of CuO: Catalytic Disproportionation of Hypobromous Acid" by Chao Liu, Urs von Gunten, and Jean-Philippe Croue, © 2012 American Chemical Society 11054 dx.doi.org/10.1021/es3021793 | Environ. Sci. Technol. 2012, 46, 11054−11061, Equations (9) and (10), available at https://infoscience.epfl.ch/record/182097/files/es3021793.pd... . To quote:

“The fitted slopes (i.e., fractions of chlorate formation over the total HOCl decay) are (18 ± 1)%, (27 ±1)%, (17 ± 1)%, and 1% for pHs 6.6, 7.6, 8.6, and 9.6, respectively. These fractions are significantly below 100%, demonstrating that chlorate formation (eq 10) is a minor pathway for HOCl decay.”

[Edit] By the way, in my opinion, this article is important due to the alleged health threat (cancer) ascribed to bromate which, reputedly, per above chemistry, could be facilitated by exposure to chlorinated water in the presence of copper plumbing (see, https://www.watertechonline.com/contaminant-of-the-month-bro... ). Note, copper is normally coated by Cu2O, but HOCl can also engage in a fenton-type reaction (see "Fenton chemistry in biology and medicine" by Josef Prousek, reaction (15), p. 2330 at https://pdfs.semanticscholar.org/2b9b/92eff9ca32556c07b1a8cc... ) with cuprous creating cupric leading to CuO, the cupric oxide being the apparent catalyst for increased bromate formation from bromide.

[Edited on 29-3-2018 by AJKOER]

[Edited on 29-3-2018 by AJKOER]

Diachrynic - 30-3-2018 at 09:59

Just wondering because I found a small air pump in my drawer.

Is it possible to just bubble air through the acid, lead the gasses into cold destilled water and clean the acid that way? Are thos fish tank bubnler-stones resistant to acid vapour?

Sulaiman - 31-3-2018 at 04:12

Yes - but;

I would consider filtering water/moisture and especially CO₂ from the air stream.

I think that the stones are ceramic so should survive a while,
but the adhesive is, I think, silicone, which 20% nitric acid will eat for lunch.

Diachrynic - 31-3-2018 at 07:54

Ok, then I just put a NaOH solution between pump and acid.

Why scrub carbon dioxide out? Is it bad to have in the acid?

metalresearcher - 31-3-2018 at 12:54

Quote: Originally posted by RogueRose

Quote: Originally posted by Sulaiman

A dry PET bottle will get hot in a microwave oven.

WHY WOULD YOU MICROWAVE ANYTHING IN A SEALED CONTAINER ?
- THAT IS ASKING FOR TROUBLE

Until the bottle ruptures inside the microwave and HCl gas is escaping and irritates your nose and mouth. Let alone the damage to the microwave.

RogueRose - 31-3-2018 at 13:15

Quote: Originally posted by metalresearcher

Quote: Originally posted by RogueRose

Quote: Originally posted by Sulaiman

A dry PET bottle will get hot in a microwave oven.

WHY WOULD YOU MICROWAVE ANYTHING IN A SEALED CONTAINER ?
- THAT IS ASKING FOR TROUBLE

Until the bottle ruptures inside the microwave and HCl gas is escaping and irritates your nose and mouth. Let alone the damage to the microwave.

No, there is no danger in this. If you take a 2L bottle, fill it 1/2 full, then squeeze remaining air out of it and screw lid on. There is 1L of expansion room for gas be it CO2 or HCl. When the gases start to expand you can see the bottle start to grow to original size. It is absolutely impossible for it to generate 1L of gas in 1-3 seconds with 1000watts of energy. I did 30 second heating "bursts", removed, shook to mix heated areas, replaced & repeated. I watched the bottle the entire time and only once after the 9th heating did it start to expand a little. When I removed the bottle, there was no pressure in the bottle b/c it still had at least 800ml of expansion room left.

Geez, I can't believe this has to be explained to some of you guys. This would be different if it was in a glass bottle, completely filled, then that would be dangerous. There is a reason they test propane cylinders they way they do, with about 90-95% water filled so there is less energy potential in the container if it ruptures during the test. What I'm doing is kind of the opposite, but since it is flexible, I reduce the volume by squeezing it down in size instead of filling with water.

aga - 31-3-2018 at 13:32

Higher temperatures requiring glass or other materials (like steel) is required to make some reactions happen at all.

Other phenomena happen at most temperatures, such as the evaporation of water at well below it's boiling point.

HCl can likely be distilled using a plastic water bottle and the cut-off bottom of a bigger water bottle containing hot water that you continually renew from a kettle.

It will be a Very slow process, yet should work.

If glass is required for any Chemistry to happen at the Speed you want, then you got to get some glass.

Now, Desert Island scenario. Just landed. Needing to distill some impure HCl ...

i'd harvest some plastic bottles from the beach (there WILL be 1000s)
use the biggest round bottle full of seawater as a lens
focus the Sun on a chunk of flat rock
bite off the bottom half of another big bottle
fill it with seawater, place it on the hot rock,
get a smaller bottle and stick some HCl in it
stick that in the hot water bath at an angle
Get another bottle and bend it at an angle, add a little seawater
hold the opening onto the opening of the boiling flask
continually splash seawater onto the bottle i'm holding.

Most of the simpler things can be done in many different ways.

*if i'd been there for about 40 days i'd use the glass retort i made with the forced-air charcoal furnace while sitting on my porch under a ceramic-tiled roof, sipping hooch, occasionally visiting the bathroom.