# Recycling HCL/CL



## wop1969 (Mar 25, 2009)

I wanted to know of someone could answer this one.


After droping and filtering gold with SMB from HCL/CL solution, can you take the now clear and clean HCL/CL and let it sit will the CL gas off all the way over time?

If so is it safe to reuse the old HCL in and AP solution? and will it be capable of desolving gold any more then a fresh batch of AP?


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## Lou (Mar 25, 2009)

As you use the HCl, it will pick up copper and other basemetals. This consequently means that any gold dropped from it will be of lower quality.

It is not advisable to let it sit around as it off gases hydrochloric acid, which is very corrosive to metal. If there is chlorine present in the mixture, that will also slowly leave the solution, depending on the temperature and concentration of chlorine gas present.


Lou


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## wop1969 (Mar 25, 2009)

Lou, thanks for answering but you missundestood me (kinda),

Take AuCl and drop gold with SMB, after that the waste is clear and contains no metals (at least my last batch didnt), now if you wanted to reuse it for a ACID PEROXIDE solution you cant, as I found out that it will desolve gold cause it still has some clorox in it, so what I need to know is if I let it sit after preciping the gold out will the Clorox gas off so I can take the leftover HCL, add peroxide to it and use it for ACID PEROXIDE now? And never waste any acid at all.

If it will gas off, how long would it take?


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## wop1969 (Mar 25, 2009)

in the above post I forgot to ask about the SMB that was added to the AuCl, what happens to it if you leave the waste sitting??


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## butcher (Mar 26, 2009)

I would guess that you would have table salt water NaCl, sodium sulfate, S02 gas , chlorine gas maybe sulfuric, maybe some HCl and water in solution,and any base metal contaminates as soluble salts
HCl +Cl + H2O + Na2S2O5 = 
NaCL + NaSO4 + H2O and gas of SO2 & CL 

or Na2HSO4
or
Na2SO4 maybe some H2So4 or ( little HCL) and NaCL

maybe acidic NaHSO4 sodium bisulfate

then there is the NaClO bleach in small amounts beside being oxidizer making table salt and some what neutralizing previous solution 

this is starting to fry my brain 
  
I am not that good at balancing equations so I can be somewhat off here.
the Hcl will gas off or boil out before any of the sulfur compounds 
I have used it boiling and adding an oxidizer, to break down scrap for recovery picking up metals higher in electromotive series, letting the metals lower in series precipitate, incenerate the powders (chlorides)and (sulfides) before treating with other acids, this seems to help me save a little, getting a little bit more for my buck, on a compound of metals. maybe someone else can balance this a little more my chemistry is not that good here.

maybe I am sticking my foot in my mouth again? :shock:


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## wop1969 (Mar 26, 2009)

butcher said:


> maybe I am sticking my foot in my mouth again? :shock:




about like me mostly everytime i post, but Im learning


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## Irons (Mar 27, 2009)

wop1969 said:


> butcher said:
> 
> 
> > maybe I am sticking my foot in my mouth again? :shock:
> ...



I can put my foot in my mouth and step on my crank at the same time.


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## wop1969 (Mar 27, 2009)

Irons said:


> wop1969 said:
> 
> 
> > butcher said:
> ...




:lol:


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## Emporio (Jun 30, 2013)

butcher said:


> I would guess that you would have table salt water NaCl, sodium sulfate, S02 gas , chlorine gas maybe sulfuric, maybe some HCl and water in solution,and any base metal contaminates as soluble salts
> HCl +Cl + H2O + Na2S2O5 =
> NaCL + NaSO4 + H2O and gas of SO2 & CL
> 
> ...



How can i dispose this solution?


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## FrugalRefiner (Jun 30, 2013)

Emporio said:


> How can i dispose this solution?


Try this thread in the Safety section: Dealing with Waste

Dave


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## chlaurite (Jun 30, 2013)

Lots of threads on disposal around here, but the simplest (for small amounts)? Just let it dry to a powder, and throw the powder away. Bonus eco-points if you at least put it some sort of waste-type container (like a paint can) and turn it in as "assorted chemicals" waste (my town has a no-fee disposal day twice a year, many do something similar).

FWIW, depending on what you started with, that powder most likely consists of mostly copper salts, which you may want to recover as metallic copper. Not worth _much_, but *making* a few bucks a pound beats *paying* it for disposal. 8)


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## FrugalRefiner (Jun 30, 2013)

chlaurite said:


> Lots of threads on disposal around here, but the simplest (for small amounts)? Just let it dry to a powder, and throw the powder away. Bonus eco-points if you at least put it some sort of waste-type container (like a paint can) and turn it in as "assorted chemicals" waste (my town has a no-fee disposal day twice a year, many do something similar).
> 
> FWIW, depending on what you started with, that powder most likely consists of mostly copper salts, which you may want to recover as metallic copper. Not worth _much_, but *making* a few bucks a pound beats *paying* it for disposal. 8)


Chlaurite,

I'm afraid drying to powder isn't good enough. You just create dehydrated versions of water soluble salts. These salts can easily be rehydrated by rainwater and flow back into streams and groundwater, and they can be very toxic.

To render them safe, the acidic solutions have to have their pH raised to above neutral to convert the soluble metal salts to insoluble oxides / hydroxides. Read the thread I linked to for a more complete explanation.

In my opinion, turning final wastes in on an amnesty day doesn't earn bonus eco-points. It should be considered a requirement.

Dave


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## Emporio (Jun 30, 2013)

FrugalRefiner said:


> Emporio said:
> 
> 
> > How can i dispose this solution?
> ...



Thank you!


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