Making copperas

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glondor

Well-known member
Joined
Jun 13, 2010
Messages
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Hey all. I want to start making my own precipitant for gold. I understand from Butcher copperas is easy to make. My question is about the Iron needed. I would like to use something standard and repeatable. Would common Iron nails from the hardware store work? What would you recommend as an easy to get and reliable Iron source. Just plain common ordinary non coated nails. If so, how much acid to iron should I use for 2 pounds of nails. How long does it take to make? Would heat speed it up? How much copperas would I get from this? It should be stored in dilute sulfuric (covered) correct? Cheers Thanks.
 
Welcome to the forum glondor. Hoke is available as a free download in my sig link. Also note the search box in the top corner. :twisted: :twisted: :twisted:

I'm just messing with you man. :mrgreen:
I've heard them mention the steel from transformers before but not sure about the nails. It is a good question though. I haven't used any yet i'm still learning the smb route. It does come in handy for testing. Someone should do a good vid or pdf on it.
 
Thanks Palladium....... I did not see the search box. hehehehe. The real question I guess has to do with the quality of iron and what qualifies. Iron is everywhere as well as steel, but what is a common easy to get type that works well??? I hope it is something as simple as common nails but some how I doubt it. 8) its most likely brake drums or truck axles or train wheels, maybe horse shoes......
 
I don't think that nails would work correctly. I have always used the iron laminates out of transformers. I believe you need low carbon. If you have some cpu power supplies you could use the transformers out of those or even laminates out of an electric motor. You're best talking to Butcher on this one.....he seems to be the pro!
 
Well.... I imagine the stuff at the garden store.....by not being stored in dilute sulfuric acid....may be a bit brown...Just saying.....not all copperas is copperas. 8)
 
I've had great luck with the copperas I've bought. Heck, even some off eBay was good. In fact I've had better luck with copperas than with SMB.

Positives with copperas vs SMB:

- cleaner drops

- no SO2 stink

- Pt that you can drop with copper after you've done the gold drop

Negatives:

- all that blasted water you need to dissolve the copperas (not to mention filtering the solution before dumping it into the gold chloride)

- the iron sulfate makes a mess during waste treatment.
 
I have an old cast iron frying pan that I use to convert AgCl using dilute H2SO4. The result id a dilute Copperas that I filter and crystallize. Eventually its bottom will fall out, but not before I get a 1000 ozT out of it.
 
I could not find good copperas as my garden supply stores, the copperas came in bags and was always oxidized brown (which would not work to test for, or to precipitate gold with).

Copperas is easy for me to make, and when I do I make a big batch to last me for a while.

The iron core of the transformers is a good source of iron (not steel although, steel does have iron in it I would not use it). Pure soft iron is rare, steel is very common, steel can be a mixture of metals, it may work I do not know, transformers are also a good source for copper for your scrap metal bin, the Iron laminates are usually welded, you can grind off the welds with an angle grinder or similar tool and separate the laminates, they usually have a light coating of shellac so, heat them with a torch to burn this off, I cut mine up for faster reaction in the acid, I wash them with water just prior to using (so they do not rust), electric motor's also has an iron core's (not the steel shell case of the motor, these can be used but are a little more trouble to separate, I use a chop saw to cut these.

Copperas is also called Iron II sulfate, green vitriol, ferrous sulfate, or FeSO4.

Dilute sulfuric acid is used, about 10% acid, so if your using new battery acid (about 32%), add about twice your acids volume with water, it is not terribly critical but shoot for 10% acid, heating speeds the reaction, so I heat these add as much iron to your acid as you like, and make as much as copperas you want, the excess un-dissolved iron can be removed later, heat also saturates the acid with the metal, when solution begins to concentrate a nice green color I filter solution, into a jar, the heating vessel is cleaned out and the solution returned to the hotplate to concentrate to crystals, the solution can be used to precipitate gold But I make the crystals, as they begin to crystallize a fair amount while evaporating the solution I remove them from my vessel, and return the liquid to the evaporating pot, these light green crystals I store slightly damp, storing them acidic also helps so a couple of drops of sulfuric acid is added to the plastic storage jar, with a good tight sealing lid these will stay fresh until you wish to use them.


Fe + H2SO4 --> FeSO4 + H2

Beside precipitating gold, copperas crystals are also good to test for gold in a spot plate, (the brown gold precipitant as an indicator of a positive for gold in solution, they are also good to use in a test for PGMs when gold in solution may change the colors, here gold can be precipitated out in the spot plate on a crystal of copperas, the remaining liquid moved to another spot and retested for PGM, (this is a trick Harold has shared and he explains it better than I can.


I also use the bisulfate salts (the byproduct from making nitric acid), the bisulfate salts react in solutions like sulfuric acid, so we can used the acid potassium bisulfate with water and iron to make copperas crystals.

KHSO4 + Fe + H2O --> FeSO4 + K2SO4 + H2O + H+(g)
http://en.wikipedia.org/wiki/Iron(II)_sulfate

For what ever reason, this link does not work, as it drops the last part (note it is in black text). Cut and paste if you wish to see the page.
Harold
 

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Ferrous Sulphate will drop out everything in solution that is lower on the reactivity series, than Iron, ferrous sulphate is really iron. As gold is lower on the reactivity series table, it will precipitate out Au, but also everything else under Fe

Is this a true (accurate) statement? I didn't think so. Butcher, are you out there?!!!!
 
Ferrous sulfate is made from iron, but it is no longer iron metal, iron metal has spare electrons to share, the iron in ferrous sulfate is an ion and already given up its electrons, so it will not act the same in solution as the iron metal would, I have to say the statement is false, platinum is under iron in the reactivity series and ferrous sulfate will not precipitate platinum from the gold solution (but elemental iron would).
 
Thanks for the tutorial Butcher. I will save up some transformers and give it a go. Your information as always is much appreciated. If I don't find any transformers soon I will try some chain and let you know how it goes. Cheers.
 
As a matter of convenience, you most likely would achieve success by dissolving structural shapes. They are intended to be welded, so they should not contain trace elements that can be harmful. However, even if they do, it is generally in a very small percentage (much of the structural steel, today, is remelt), so if you don't use the solution directly, contaminants will be excluded when the ferrous sulfate crystals grow. That's the nature of the process, whereby if you grow and redissolve the crystals more than once, you can achieve, for all practical purposes, pure iron (as ferrous sulfate).

If you elect to dissolve *anything* (including laminations, which are made of carbon free iron), I do suggest you filter the resulting solution prior to allowing crystals to develop. Otherwise you risk including contaminants. Carbon, for example, won't be dissolved, and will report in your crystals unless it is filtered from the solution. That can be a problem even with laminations, assuming they are incinerated to remove lacquer.

Harold
 
Butcher, Harold,

If I use structural steel/Iron to make copperas, would traces of other metals precipitate during structural steel dissolution in H2SO4 and can be separated by filtering?

What other traces may still be dissolved/remain in the solution making coppers "dirty" when made out of structural steel?
 
Alentia,
My suggestion just use transformers they are easy to find and readily available and the close to pure iron,

Steel although it is high in iron, but is not just iron; steel as I understand, is just a name for a metal of iron that has been changed chemically to produce a stronger metal, or a metal of different properties than pure iron.

Steel can be many forms mostly iron but can also have other metals, or other elements involved, like carbon, it can also have silicon, phosphorous, or metals like nickel, chromium, vanadium, manganese, molybdenum, tungsten, cobalt, possibly other things, some of these may be insoluble in dilute sulfuric, but some are not, and may react with undesired results in our refining of our gold.

The more pure Iron is not used much nowadays as it was back in history or in the days of blacksmithing to make tools, pure Iron is very soft (softer than aluminum), The steels we use today are made to give strength or other useful properties to the iron in them.

Transformer or motor Laminates (the soft iron sheets) are very close to pure soft iron, transformers are very easy to find, I would use them to make your ferrous sulfate.

When doing blacksmithing I look for iron to make things out of, like old iron from things made by a blacksmith before modern steel, or horse shoes, railroad spikes, wrought iron, and other things with properties closer to iron than steel, I know how these work when blacksmithing, but I do not know how they would work to make ferrous sulfate to precipitate gold.

I really do not know how well steel would work to make ferrous sulfate (copperas) to precipitate gold, it would make a ferrous sulfate and could be filtered and recrystalized to a higher purity, but I do not know if some of the other more reactive metals would be involved when you made the crystals.
 
Ok, Structural steel is coded 1080

Following is the composition:
Note on Lead (Pb), Copper (Cu), Boron (B) content:
'L', 'C', or 'B' may be present between the second and third digits of the SAE/AISI number (IE, 12L14) to indicate the presence of Lead (0.15-0.35), Copper (0.20 min), or Boron (0.0005-0.003).
P and S are maximum values, unless a range of values is specified.
P = phosphorous, C = carbon, Mn = manganese, S = sulfur. All values are percentages.

AISI
SAE - 1080
UNS - G10800
C - 0.75-0.88
Mn - 0.60-0.90
P - 0.040
S - 0.050

Lead will enter the reaction creating Lead Sulfate as precipitant
Copper will be precipitated by Iron
Carbon should be as precipitant
Mn will dissolve:
Mn(s) + H2SO4(aq) → Mn2+(aq) + SO42-(aq) + H2(g)
S will exist as gas
S + 2H2SO4 ------> 3SO2 + 2H2O
P will remain in the solution as Phosphoric acid [H3PO4]
20 P + 40 H2SO4 = 20 H3PO4 + H20 + 40 SO2
Reacting with Fe we get Ferrous Phosphate as precipitate
Fe + H3PO4 = Fe3(PO4)2 + H2
B will not react with H2SO4 unless it is really hot

This will only leave us with Mn in the solution of 0.6-0.9% to create Copperas.

Are there any negative effects to have Mn mixed in crystals for gold precipitation?
I wonder how visible are Mn particles when Mn2(aq) dries out?
Will Mn form something else in the reaction of multiple elements present?
Can Mn be simply sifted through the mesh?
 
Alentia,
Thanks, Nice work,

I would think since you will have acidic solution left as you crystallize the ferrous sulfate, the more reactive metal would stay in solution, and not crystallize, crystals can also be re-dissolved in a little hot water and a few drops of acid and re-crystallized to a higher purity the second time.

S + 2H2SO4 ------> 3SO2 + 2H2O
I am unsure but I do not think the sulfur would make SO2 gas unless the sulfuric acid was highly concentrated and heated to the point of boiling off SO2 gas (I am unsure), but if sulfur did not dissolve letting solution settle with carbon or other insoluble material you should be able to decant and filter the solution.

I still cannot say there would be no problems using Structural steel coded 1080,
But from your well-written post it does look like it would work to make good ferrous sulfate.
 
OK!
Hi Everyone!
I have done some test and nails work's great for me:)

This is what I'v done:

- 500g of nails (smaller =better)
- 750g sulfide acid (condensed)
- 2500ml of water (distilled =better)

1. Place nails in to your flask.
2. Add water.
3. Add acid (slowly!)

1. Warm this up on water bath and wait until nails almost gone.
2. Warm solution filter with paper filter.
3. Still warm filtered solution pour in to 1500ml of alcohol (i used IPA).
4. Stir well.
5. Crystals will show up in flew seconds.
6. Filter the crystals.
7. Rise them with 100ml of alcohol again and make them dry.

You have 2000-2250g of clean copperas(FoSO4+7H2O) in your had:)

Photos of my first attempt:

Nailsafterreaction_zps4beb0e79.jpg

Copperas_ready_to_dry_zpsad6d74e7.jpg


I hope this help.
Reagrds Mice

P.S
According to my source book if you want to make him really dry, You have to place copperas in flask and warm up (100C)(melting point around 64C) until he lost 30% of his "firs dry" mass.
In another words:
Wait until alcohol evaporate and then weigh, place him in flask and warm up (100C) and wait until his dry mass drop around 35-36%. Crush and hold him in tight container.
You can hold copperas unter H2SO4 cover (Thx Geo!)
 
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