# poor man's HCl: produce from rock salt; 12 v. DC



## scwiers (May 17, 2008)

went to the Local Lowe's building supply today, and I didn't buy a gallon of 29% HCl; 7$ is just too hard on the budget. Bleach oxidizer, though, is still mercifully below 2$/gal.

So... the problem is... making it from rock salt in solution, and making an effective chloride solution using a 12-V battery charger.

Basically, the main expense is going to be graphite cathode/annodes--prolonging their lives, as these, too are $$


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## Anonymous (May 17, 2008)

The chlorine boils off at the anode, I tried it. But, I may have missed something.

also the bleach is only a 5 percent solution. Better to buy pool chemicals and make your own.


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## Platdigger (May 17, 2008)

Sulfuric + salt + heat.................hcl...........?

Anyone know an easy way to purify sulfuric from old car batteries?
Randy


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## Andrew W (May 17, 2008)

Platdigger said:


> Sulfuric + salt + heat.................hcl...........?
> 
> Anyone know an easy way to purify sulfuric from old car batteries?
> Randy


Maybe you could let all the lead and junk settle, decant, and then filter.
After that you could try this:
http://www.sciencemadness.org/talk/viewthread.php?tid=3722&page=1<----talks about using H2O2 to clear up the black drain cleaners.


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## Anonymous (May 17, 2008)

I think old batteries will have most of the acid tied up as lead sulfate.


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## Platdigger (May 17, 2008)

Is there any way to remove the lead without destoying the acid?
What about freezing?
Randy


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## scwiers (May 17, 2008)

a twist: forget graphite annodes/cathodes, all of mine are busted, or nearly disintegrated, anyways. I'm going to try some lead ingots I've got hiding somewhere, instead. The theory is that current should flow, and at least some Cl gas should redisolve in the liquor. And lead itself moves pretty slowly at both + and - ends; isn't that what car batteries are all about?


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## Anonymous (May 17, 2008)

thats the basics of making bleach, but not hcl. It is cheaper to just buy it.


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## Rag and Bone (May 17, 2008)

$7 is alot for HCl. Lot's of places have it for less than $4.


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## Anonymous (May 17, 2008)

Yes, that may be the case, but, it is still less than trying to make it.


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## Noxx (May 17, 2008)

> $7 is alot for HCl.



Unfortunately, that's what I pay. The cheapest I've found.


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## SapunovDmitry (May 18, 2008)

I bought my HCl for 4 $ for 500ml . I bought about 6 liters. Then i got to the subway  and went home. It was a technical grade acid. I think there is a difference between technical grade and lab grade in prices.But i think they work the same for us.

Btw. If there is a way to make your own acid i think it is worth discussing it here.  Cause in some coutries you will have to work hard to find muratic. I know only one place in Russia when you can buy it for real money without organization. I am sure noone will close it but in case someone tries alot of people will have problems with chemicals. Cause you have to get special licenses to work with HCl. But in return we have no problem with Nitric. :wink: You can buy it wherever school equipment or chemicals are sold. It's cheap.


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## Oz (May 18, 2008)

Seems odd they are more worried about HCL than Nitric. Do you know why?


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## markqf1 (May 18, 2008)

Mmm, ...that must mean that you have to have a license to clean or etch concrete. :shock: 

Mark


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## OMG (May 19, 2008)

Scwiers,
Titanium anodes are supposed to resist dissolving in a setup like that. I am trying the exact same thing you are, but I'm still waiting for my titanium to get here. If you are bubbling the chlorine off and the solutions ph is about 4 - 5, the reaction with the water will be Cl2 + H20 -> HCl + HOCl. When the ph is below that the Cl2 doesn't stay in the water very well. I'm doing mine in a 2 cell setup so no lower metals get involved (ie sodium). I have a bunch of other ideas I'm going to test out. I'm going to see if it's possible to safely do the H2 + Cl2 -> 2HCl reaction (using a flash to initiate the reaction). Once I get my titanium and get back into it, I will post my results.


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## scwiers (May 20, 2008)

in that reaction, I know NaOH is being made, too.


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## Anonymous (May 20, 2008)

Light I believe will ignite hydrogen and chlorine.


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## scwiers (May 21, 2008)

Another approach might be thin-film membrane separating the annode from the cathode. As I muse out-loud again to myself, though, it's starting to dawn on me why the stuff is $$, at least in my neighborhood. Add in the cost of the NaCl (20 lbs, say, for 4$; the kilowatts used [?], inevitable loss due to venting of Cl, H+, and whatever, just to end up with a gallon or two of HCl?


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## OMG (May 21, 2008)

I have been using a clay flower pot for separating the two cells. It works okay, but after a while it seems to get clogged up and not allow the ions to pass very easily (ie reduction in current flow).
I had quite good results when I was dissolving black sands in the anolyte and just allowed the chlorine to bubble into solution. It got absorbed quite well. I also had to add peroxide. I believe it made the HOCl into HCl + O2, because when I added the peroxide it dissolved significantly faster (although the chlorine got absorbed less). As a side note, I think the peroxide also equalized the ratio of FeCl3 to FeCl2. The only method I used for measuring how fast it was dissolving the black sand was how much "sand" was getting broken down into "silt". Once I went through a few carbon anodes, I quit, but I had made about half the sand get broken up (by dissolving the iron) and had about half the container as very fine silt.
** I figured out one time it would take 17cents worth of electricity to make the equivalent of 1 gallon of 32% HCl (under perfect conditions)
I will be using previously dissolved base metals as the source of chlorine instead of NaCl, and hopefully be able to combine the H2 and Cl2 together. Basically wasting nothing except electricity.


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## Bernie Foley (May 22, 2008)

OMG,
Please be very carefull Combining these two. I believe this reaction gives off a tremendous amount of energy and heat!!! Any larger quanity may
give a rather big explosion!!...Maybe some of our best chemists could
comment. There maybe a way to control the reaction.
I hate to hear of anyone getting hurt! I think hydrogen and florine is about the same. Was used as rocket fuel till too many got blown up!
Have a good day,Bernie


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## OMG (May 22, 2008)

Bernie,
Ya it is a very exothermic reaction. Industrially they are called "HCl ovens". I am hoping the reaction can be done with only small quantities. I will set something up such as a flash from a camera to flash in the chamber intermittently (which aparently is all that is needed to make them combine), consuming the small amounts of Cl2 and H2 produced from the electrolysis. It will be a bit of trial and error. The HCl gas is supposed to be so attracted to water that it will actually make a partial vaccuum in order to dissolve itself. There will be more free H2 and this vaccuum, I'm hoping, will pull the excess H2 into the reaction chamber (which will be right above the anolyte). I am also hoping that the over pressure of H2 in the catholyte half cell will also prevent the HCl gas from getting over there.


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## Bernie Foley (May 23, 2008)

Hi,
Glad you are aware..Maybe invent an engine to run on it and the exhauste
will be HCL!! We have materials if you know which ones to use to build such a thing! That would kill two birds with one stone!! Probly make alot of usefull heat also!...Good luck maybe have someone else-chem engineer or like person to advise of problems....Be safe...Bernie


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## OMG (May 23, 2008)

I like that idea!! An H Cl engine.
Hmm. something to think about in the furture.
Maybe the energy released can be used as some of the power for the electrolysis.


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## Bernie Foley (May 24, 2008)

omg,
Guess you'll have to put a generator on it. With some serious thought and some good luck i think you could do it!...I can help on generators not chem. engineering..I rebuilt them for 28 yrs.....Bernie


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## P_CARROLL (May 26, 2008)

pool supply stores have the best prices on hcl. I get ti fir 12 bucks for a case of 4


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