Electrochemistry Child safe gold recovery with DC current.

[ryobie1]

I have been enjoying the time spent de-plating gold with the standard sulfuric cell. This has all been done outside and with out my kids around. They of course are at the age where they want to do everything I do. So in order to continue I have to involve them but with out the risk of acid. It seems to be working and safe. No refining just recovering.

Here is what I have come up with for a child safe recovery method:

Salt water for the electrolite in the cell, Graphite block for the cathode and stainless steel or copper for the anode. I start with water in the cell and add salt slowley till I see the amps get to about 5. It does tear at the stainless bad after a cuple hours of continuous use witch could be a problem later. I notice if I don't run the stanless too long ther is negligible contamination. If I let it dry and rest for a while it will go again. The copper doesn't seem to bad and for me, it's an easy-er contamination to deal with but the copper is a little harder to get than stainless and letting it rest does not seem to slow the deterioration like the stainless. The graphite is neerly untouched and seems to be growing cristal like structures from the salt but washes off easaly and contamination semms little to none. Getting the gold out of the solution is very simular to the acid cell. (dilute, rinse, decant, repeat)

The gold does not turn black in this cell but instead turns the solution one of the most beautifull, soft yellows I have ever seen. (Makes contamination very easy to spot.) Also the gold doesn't seem to settle untill I dilute the solution 1:1 with distilled water. Even then the gold still is slow to sink. Not only is this safe recovery but budget style too.

Again, I have not refined any gold recovered with this method and you have to watch the de-plating material close. Carefull to remove it when the gold has been de-plated. It will desolve the material under the gold down to nothing, seriousely contaminating your solution.

This method is far slower and requres more atention than the standard sulfuric cell and can not be turned up due to heat. higher current attacks the graphite. but this can be done indoors around childeren. As far as I can tell the only polutant from this is hydrogen gas. Please do further research on this before involving childeren. There could be a serious risk I don't see.

 

[qst42know]

Have you tested this yellow solution with stannous for dissolved gold?

It is possible to put gold into solution with electricity in salt water.

 

[ryobie1]

I have not tested the solution. (I haven't made SC yet) but the gold plated items are clearly being de-plated into the solutiond with the current. The main problem with this is the the anode disolves contaminating your gold. This has not replaced my sulfuric cell. It is a fun low budget toy.

The kids and I have put all are batches together into a 5 gallon aqarium with a single powerhead pump and very bright light. I can't explain it other than living gold. This is worth doing just to see the color patterns it makes. You can make the color with around 50g of heavy plate and 1p of water but the more you de-plate the more sparkel the water gets.

 

[samuel-a]

You defintly have gold in solution.

Basically, what you have built is a twisted version of a Fizzer Cell.

 

[butcher]

Caution, do not do this in a house on enclosed environment with your children, as you can generate chlorine gas (splitting salt NaCl), this chlorine can be dangerous, it can also contaminate your home.

You can also split water to form Hydrogen gas, and oxygen.

Another byproduct can be sodium hydroxide from the reaction.

Conditions of cell and current will be a factor in what gases you will form.

Salt water would normally be safe around children, but you no longer have saltwater when you’re doing electrolysis on it.

Chlorine you’re generating will dissolve gold into solution.

 

[ryobie1]

You are 100% correct. You can get chlorine gas from chloride salts with electrolysis. Not to mention caustic alkali as a co-product.

Electrolysis in salt water does make clorine but You would have to find a way of preventing the chlorine (forming at the anode) from re-mixing with the sodium hydroxide and hydrogen (formed at the cathode). That would be very tricky to do with the equipment I have described.

I stand by my statement of the method described. "Safe" but revise to add: Adult supervised. Assuming you don't go large scale.

If you had the cathode in one room and anode in another, connected the two electrolites with a small tube and introduced dc cuurent. The room with the anode would be a reall bummer place to be.

This is why every one here stresses over and over that you read, read more, learn and understand the chemicals you intend to use before you touch them.
Chemistry is no joke. Something as simple as table salt will kill you.

 

[ericrm]

ryobie
can you tell more about the danger because to be honest with you, between using 98% sulfuric acid and table salt, i rather go with salt anytime...
if this is very dangerous can you convince me not to use it
thank you

 

[Geo]

sodium alone and chlorine alone are two of the most deadly elements on earth but when you combine them together you get table salt. something that's necessary to almost all life on earth. when you separate table salt to its individual elements you have created two dangerous elements again.

 

[ryobie1]

Thanx geo, I don't think the danger could be said any more clearly.

When you choose what process is right for you. Learn as much as you can about it. Think about the anode being consumed in this process. This has not replaced my sulfuric cell. It's just fun with my kids. If some one knew of a commin material that could be used as an anode I would be interested to read it.

 

[Dr. Poe]

Sodio-gold precipitates as the yellow gold+3 oxide above pH 6.5. Basic copper chromate CuCr2O7-2CuO-2H2O Could have formed; It's insoluble in water, ammonium hydroxide, dilute acids, is bright yellow. It dissolves in strong acids (as also does gold oxide).
Separate it, dissolve in concentrated HCl then test for gold with stannous chloride. Then stick a nail in the acid and see if it turns red from copper. I think it might be both mixed together. The chromium coming from the stainless steel and possibly also the copper. You stated that you have used both for anodes. In case the gold is in an oxide state, be sure and NOT use ammonium hydroxide as an explosive compound will surely form. Remember that bleach is made from salt and electricity so eventually the salt will not be safe to touch or to breathe.
Just trying to help. Dr. Poe :mrgreen:

 

[joem]

8) just liking this

 

[Palladium]

http://www.freepatentsonline.com/4612093.html

 

[Traveller11]

Hello
I've been following this thread with interest and hoping I might be able to apply its basic principle to my situation.

If this cell has the capacity to put gold into solution, can it put all of the gold present into solution? Will it put base metals into solution, as well?

The reason I am asking is I have concentrated placer material that is quite rich in micron sized gold flakes but it also contains iron in the form of the oxides magnetite and hematite. Other than than, there are no metals in it, outside of a bit of PGM's.

If the solution in this cell can have its gold precipitated in the regular fashion, is it possible just to precipitate gold from the solution and not iron?

 

[Geo]

the process being discussed is the electro stripping cell. it is used to strip gold from gold plated material. its not the same as dissolving free standing gold.

 

[Traveller11]

Thanks geo. I did some reading and it is clear now that it is something totally different than what I conceived it to be, and not applicable to my needs at all.

 

[Traveller11]

Though I must admit, the concept of putting gold into solution from sand using nothing more than salt water and DC current did have quite an attraction to it.

 

[butcher]

Though I must admit, the concept of putting gold into solution from sand using nothing more than salt water and DC current did have quite an attraction to it.

It sure does sound attractive, and if it would work the mining industry would have used it, instead of the methods they do use, I say it would be a waste of time.

Unless the gold was made the anode, what would be the benefit? Even then the gold would need processing before melting to an anode (unless the gold content was high and the silver content was very low, even then a membrane cell would be needed to recover the gold and separate it from some of the base metals.
Unless the gold was of very high purity (almost pure gold anodes), at which point you would be better off using gold chloride solution as your electrolyte (to get the gold to a state of higher purity).

With your sand and salt cell (trying to recover gold), if you had any other metal as the anode that would dissolve into the chlorine and which would form chlorides they would contaminate solution, and also cementing out the gold from solution back into the sands any dissolved gold back into the sands, the base metals could also plate out at the cathode.

If all your doing is making chlorine gas, or chlorine in solution to dissolve gold, there are several way's to generate chlorine, but why, hypochlorite or chlorine is cheap, why not just add them to your solution if that is what you needed.

If the gold had much silver you would not have very good results, as the silver chloride would passivate the gold anode with a crust of silver chloride, and slow o stop the oxidation process.


If your talking about separating gold from sand you need to learn to pan gold, or use some other gravity method, then process it to remove the base metal, then if you wished to make anodes, and use a concentrated brine with a membrane (5 micron Coors cup) in an electrolytic cell, that would possibly work, but even then it seems like a lot of trouble, I would just use in-quartering then nitric and aqua regia to refine my panned gold.

If your not talking about placer gold in your "sand" then that would be a totally different set of problems.

 

[MysticColby]

I've read somewhere that Sodium Carbonate (or bicarbonate) is a better additive than NaCl for electrolysis of water. May not work for this application, but it would make it a little safer (no chlorine produced).
Hydrogen and Oxygen gasses generated should definitely be vented.

 

[Traveller11]

http://www.artisanalmining.org/casm/sites/artisanalmining.org/files/publication/Veiga_Replacing_Hg_in_ASM%20Operations.pdf

Would some of you please look at pages 48 & 49 on this site regarding the SALTEM electrolytic gold recovery process? It was patented by an organization in Brazil but I can't seem to find anything on it.

If it was depositing gold on the cathode, wouldn't the cathode need to be separated from the pulp to keep the gold from simply falling back into the pulp?

 

[Traveller11]

I have been enjoying the time spent de-plating gold with the standard sulfuric cell. This has all been done outside and with out my kids around. They of course are at the age where they want to do everything I do. So in order to continue I have to involve them but with out the risk of acid. It seems to be working and safe. No refining just recovering.

Here is what I have come up with for a child safe recovery method:

Salt water for the electrolite in the cell, Graphite block for the cathode and stainless steel or copper for the anode. I start with water in the cell and add salt slowley till I see the amps get to about 5. It does tear at the stainless bad after a cuple hours of continuous use witch could be a problem later. I notice if I don't run the stanless too long ther is negligible contamination. If I let it dry and rest for a while it will go again. The copper doesn't seem to bad and for me, it's an easy-er contamination to deal with but the copper is a little harder to get than stainless and letting it rest does not seem to slow the deterioration like the stainless. The graphite is neerly untouched and seems to be growing cristal like structures from the salt but washes off easaly and contamination semms little to none. Getting the gold out of the solution is very simular to the acid cell. (dilute, rinse, decant, repeat)

The gold does not turn black in this cell but instead turns the solution one of the most beautifull, soft yellows I have ever seen. (Makes contamination very easy to spot.) Also the gold doesn't seem to settle untill I dilute the solution 1:1 with distilled water. Even then the gold still is slow to sink. Not only is this safe recovery but budget style too.

Again, I have not refined any gold recovered with this method and you have to watch the de-plating material close. Carefull to remove it when the gold has been de-plated. It will desolve the material under the gold down to nothing, seriousely contaminating your solution.

This method is far slower and requres more atention than the standard sulfuric cell and can not be turned up due to heat. higher current attacks the graphite. but this can be done indoors around childeren. As far as I can tell the only polutant from this is hydrogen gas. Please do further research on this before involving childeren. There could be a serious risk I don't see.

A question for you. If you dissolve the material under the gold, you say the base metals seriously contaminate your solution. From this contaminated solution, does only the gold deposit itself at the cathode or do the base metals come out of solution and deposit at the cathode, too?