HCL+Clorox ratio, conflicting numbers

[sng]

I've read that the correct ratio is 4parts HCL to 1 part Clorox in a few places, but lazersteve said he used 100ml HCL+10ml Clorox in this thread: http://goldrefiningforum.com/phpBB3/viewtopic.php?f=52&t=416&p=3486&hilit=clorox#p3486.

100ml/10ml is nowhere near a 4:1 ratio. Usually I'd trust the most commonly cited ratio (4:1), but lazersteve seems to know his stuff and could very well be correct over everyone else.

Also, how much HCL+Clorox is needed per unit of gold powder? I've looked in the reaction list of this document (http://www.scribd.com/doc/2887935/GOLD-REFINING-FORUM-HANBOOK-VOL-1) and done a search of "acid+clorox" but have been unable to determine how much needs to be used. Can I add slowly and stir until the gold is fully disolved?

Also, while you're here, how much SMB is needed per unit of dissolved gold. I'll try to find this myself, but am asking anyway in case someone decides to answer before I can find the answer for myself.

Edit: SMB= Sodium MetabisulfAte or MetabisulfIte? I've seen it written both ways... one has to be the wrong chemical, no?

 

[Barren Realms 007]

I wouldn't go by a known ration I feel you have this confused with AR. You want to add just enough to dissolve your gold and then warm the sloution or let it set outside till the chlorine has disipated and then addd your SMB to percipitate you gold out. Generly gram of SMB per gram of gold. You want metabisulphite not sulphate.

 

[Sucho]

check these links, compare molecule structures and try to make equations...gold halide(cl-) complex is reduced by SO2 ... from which salt could SO2 develop,when you are using water and HCL ? or try the search box ..

sodium metabisulfite

http://en.wikipedia.org/wiki/Sodium_metabisulfite

sodium sulfite

http://en.wikipedia.org/wiki/Sodium_sulfite

sodium sulfate

http://en.wikipedia.org/wiki/Sodium_sulfate

 

[sng]

I know what Aqua Regia is, what piqued my interest in HCL+Clorox was that it enabled me to dissolve gold without making Aqua Regia. I'll need nitric acid to separate inquarted silver and gold, but HCL is much easier to find (and less expensive) than nitric. Bleach is obviously more readily available than any acid used in gold refining.

I'm confused, how do I make a HCL+Clorox solution if I don't know how much of each to add?


Edit:

HCL can not dissolve gold. This means that the chlorine is what dissolves the gold and that the HCL is just there to dissolve the chlorine? If too little HCL is used the chlorine will escape in gaseous form, causing the dissolved gold to reprecipitate. If too much HCL is used, the chlorine will be too dilute to dissolve the gold powder. Am I overthinking this?

 

[Sucho]

its enabled by free chlorine , because in bleach is included this compound

http://en.wikipedia.org/wiki/Sodium_hypochlorite

which interracts with your acidic solution and free chlorine is enabled- chlorine gas could oxidize gold

 

[sng]

I understand how the reaction works. What I need, is a recipe. Without a recipe I have no way to know whether to add more HCL or more bleach should the reaction stop before the gold is fully dissolved. Trial and error is a sure way to use more material than necessary. Everything else pertaining to gold refining has had a general recipe to follow, while HCL+Clorox's recipe is "HCL+Clorox".

 

[Barren Realms 007]

There is no set recipie for this trial and error and experience is how you come up with your formula.

 

[Sucho]

it depends on concentration of NaOCl...you can count it...i have never used hydrochloric-clorox, but in my opinion , you can use 1:1...or you can see it during reaction...its all about equilibrium ..you can speed up/slow down/end the reaction by adding reactants/products/catalysators/etc...every system is trying to achieve state with the lowest energy...

 

[sng]

Ok... not the answer I was expecting . So long as adding too much of something can't somehow harm the gold, I think experimentation could be quite fun. Worst case, I waste acid or bleach but still end with dissolved gold right? And Sodium Metabisulfite quantity won't change because that is dependent on the amount of dissolved gold which will remain unchanged regardless to how much HCL/Bleach I use.

I guess I'll just start small. Cover gold powder with minimum amount of HCL, add small amounts of bleach, and stir often.

TYTY

 

[Barren Realms 007]

Ok... not the answer I was expecting . So long as adding too much of something can't somehow harm the gold, I think experimentation could be quite fun. Worst case, I waste acid or bleach but still end with dissolved gold right? And Sodium Metabisulfite quantity won't change because that is dependent on the amount of dissolved gold which will remain unchanged regardless to how much HCL/Bleach I use.

I guess I'll just start small. Cover gold powder with minimum amount of HCL, add small amounts of bleach, and stir often.

TYTY

Yes to your last part.

 

[oldgeek]

I have used the 4:1 ratio without issues.
I added the bleach to the HCL in increments.

An important part to remember before using SMB to drop your gold, is to dilute your AuCl3 solution 3 times over with water. You may need to refilter after dilution as some silver chloride may form (I learned this from a video on lasersteve's website, you should also watch it.)

Mix up your saturated SMB solution and add some to your AuCl3 while stirring. You then test your AuCl3 with stannous Chloride to ensure you have dropped all of your gold.

I learned ALL of this from lasersteve's guided tour. (link provided below)

http://goldrefiningforum.com/phpBB3/viewtopic.php?p=6873#6873

Click on the "reactions list"

 

[lazersteve]

Here's a few old links:

How much HCl and Clorox to dissolve gold?

Guided Tour

The bleach is not all added at once, it's added in small increment as I stated before. If you add a large dose (eg: ~100mL), you will only succeed at making a big cloud of chlorine which does nothing towards dissolving your gold, but will choke you very quickly. The only chlorine that works on dissolving the gold is chlorine that is in the solution, not the chlorine that is floating around your lab.

Add the small dose (eg: 10-20mL) and stir until no more fizzing occurs, then let the solution settle a minute and see if the gold is all dissolved. If it is not then add another small dose of bleach, if the gold all dissolves on the first dose, don't add any more bleach.

Too much bleach will prevent the gold from precipitating and will also interfere with the stannous chloride test.

Steve

 

[donnybrook]

I was told many years ago that the ratios (SMB in distilled water) to recover gold in a prepared solution was 110grams of SMB to 1 litre of solution of distilled water to recover 60 grams of gold.

Your weight measures including that for an ounce of gold (28 as opposed to 31.2 grains) are different so you may have to convert. That would be a laboratory formula and not necessarily what I would use myself. My solutions are broken down with 10 parts water before adding the SMB.

donnybrook

 

[Gratilla]

Some time back I tried both HCl + Clorox (5%+/- NaClO) and HCl + Industrial sodium hypochlorite (24%+/- NaClO); the former is also referred to as the iGoli process put into the public domain by Mintek of S Africa to discourage use of mercury by artisanal miners. I would offer you a copy of this doc, but I can't find it. A google should turn it up though.

Irrespective of the recipe, the "trick" is to add the NaClO in small increments (in line with lazersteve's suggestion) while stirring (and holding your breath). Trying to speed the process by adding large amounts of NaClO quickly will only result in a large off-gassing of Cl, wasting your chemicals and endangering your health. Basic chemistry suggests that running the process in a closed system should minimize off-gassing. I think Mintek has some equipment for this.

Also, excess oxidants (NaClO in this case) will interfere with reducing reactions such as precipitation and the stannous test. For the same reason the nitric acid (an oxidant) in AR needs to be eliminated before attempting precipitation with a reducing agent.

 

[wwjd72]

I AM NEW AND IT IS SOME WHAT HARD TO FOLLOW YOUR WORDING .I wish someone could speak like ghetto aka: at lows buy ... use i cup to 1/4th of a cup of hydrogen peroxide in your aqua Regina aka gold extraction through use of chemicals. also I just put my misc stuff in a solution of "3m heavy duty bowl cleaner"yes toilet stuff. at 4 am.active ingredient is hydrochloric acid.

 

[Oz]

Wwjd72,
If you wish conversation like that go to the ghetto, you will not find it here. If you want professional opinions about refining, stick around. If you wish to speak that way and wish others to answer you in kind, I will personally remove you from our site as you will have no reason to be here since such a sloppy method of conversation when dealing with hazardous chemicals can get someone maimed or killed.

Shape up or ship out!

 

[joem]

I AM NEW AND IT IS SOME WHAT HARD TO FOLLOW YOUR WORDING .I wish someone could speak like ghetto aka: at lows buy ... use i cup to 1/4th of a cup of hydrogen peroxide in your aqua Regina aka gold extraction through use of chemicals. also I just put my misc stuff in a solution of "3m heavy duty bowl cleaner"yes toilet stuff. at 4 am.active ingredient is hydrochloric acid.

Even I am newer at this and I still don't get what you are asking?
aka: what? :shock:

 

[rustyle]

Here's a few old links:

How much HCl and Clorox to dissolve gold?

Guided Tour

The bleach is not all added at once, it's added in small increment as I stated before. If you add a large dose (eg: ~100mL), you will only succeed at making a big cloud of chlorine which does nothing towards dissolving your gold, but will choke you very quickly. The only chlorine that works on dissolving the gold is chlorine that is in the solution, not the chlorine that is floating around your lab.

Add the small dose (eg: 10-20mL) and stir until no more fizzing occurs, then let the solution settle a minute and see if the gold is all dissolved. If it is not then add another small dose of bleach, if the gold all dissolves on the first dose, don't add any more bleach.

Too much bleach will prevent the gold from precipitating and will also interfere with the stannous chloride test.

Steve

Hi Steve,

I think I have too much clorox in the solution. How do I correct it? I have gold dissolve in solution but not drop much when add SMB. Please help!

 

[butcher]

Heating the reaction will drive excess chlorine from solution, chlorine is a gas, most gases are much more soluble in cold dilute solutions, these same gases are not as soluble in hot solutions and are driven off by heat, oxygen in water is similar we can drive oxygen out of water with heat.

 

[variable]

Here's a few old links:


The bleach is not all added at once, it's added in small increment as I stated before. If you add a large dose (eg: ~100mL), you will only succeed at making a big cloud of chlorine which does nothing towards dissolving your gold, but will choke you very quickly. The only chlorine that works on dissolving the gold is chlorine that is in the solution, not the chlorine that is floating around your lab.

Add the small dose (eg: 10-20mL) and stir until no more fizzing occurs, then let the solution settle a minute and see if the gold is all dissolved. If it is not then add another small dose of bleach, if the gold all dissolves on the first dose, don't add any more bleach.

Too much bleach will prevent the gold from precipitating and will also interfere with the stannous chloride test.

Steve

After adding second small dose of bleach and gold is still undissolved what would one do? Steve says one should stop. Should one pour solution from original vessel to a second one and put more fresh 4:1 ratio Hcl + bleach in original vessel to finish the process. So, as long as we have 4:1 ratio, there should be no problem in dropping gold with SMB from our solution in question? Would each addition of bleach (now first + second vessel) create a cumulative effect where it would interfere with SMB drop? Or putting 4:1 ratio of in the same vessel should work as long as it's not only bleach? I'm asking since I think I put too much bleach last time I processed my powder from sulfuric cell ( was not digested after first addition to was putting more bleach to finish the process ). More like 4:2.5. I did get a partial gold precipitate on the bottom of my vessel. Also, SnCl2 test is negetive for gold. However, I understand the this could be false negative due to too much bleach. Also, the vessel still shows little bit of yellow/bownish after smb drop (sorry no picture). It did seem like I had 2x treated original black powder from sulfuric cell to start with. Should I stick a piece of copper and see what else comes out or try something else such as dilution with water or anything else which would work same way to reduce bleach concentration?