Making "Copperas" - ferrous sulphate

[allanwcoty]

Thanks for all the posts. If I'm reading the charts right I don't have much room for the sulfuric to loose strength. Anybody with an answer to the by-products?

 

[qst42know]

I don't know what the byproducts of making copperas are but if you must make some you could use an electric crock pot. If your amount is small you may be able to use one of those electric potpourri cookers. Still Copperas is quite cheap it may be difficult to justify paying for heat in 20 below weather for a low price compound.

I quit processing when it got cold to keep my electric bill down. I'm definitely suffering from the refiners form of cabin fever

 

[allanwcoty]

Put 10 cups of new battery acid with about 10 small strips of iron out at 1pm at 10 degrees below F. Just checked at 3:30pm and has some slight bubbles that are forming a scum on the surface of the acid. Could be they are trying to freeze. Remaining solution has no sign of freezing.

 

[allanwcoty]

Lots to learn. First batch was not with transformer or motor laminae but with some laminae that come out of old dial phones, about 12 in a stack that goes through copper coils. They are having some action but not much. I got impatient with it out in the cold and brought it indoors and put a plastic bag over bucket and secured to allow for expansion & gasses? Inside it still is working slow but better.
Started a second batch with 10 cups new sulfuric and 2 chunks of unseperated laminae and they went to work pretty fast. Used up all of the sulfuric and crystals actually seperated the laminae and may be expanding too much for the coffee pot? Added second batch of sulfuric and will look at later. Coffeepot was very warm from the reaction. Any ideas as to the gasses being given off yet. Have a Merry Christmas everyone. allan

 

[butcher]

Made 2 quarts of nice light green / blue crystals ferrous sulfate (copperous), cutup transformer laminates small pieces, torched any varnish rinsed in diluted sulfuric/water, in 5 gallon bucket covered with new battery acid 1 part and 2 parts water, (ok if stonger at first but needs diluted sometime). we want FeSO4*7H2O. when liquid nice blue color. I pull out liquid with suction bulb to get only clean solution, put into coffee pot, not disturbing Iron on bottom, then add more acid and water to Iron for next batch later.( this can be kept going till all Iron gone)
slowly evaporating the blue solution in coffee pot on hotplate, not boiling. and not too hot ( too hot acid seperates making unwanted white powder), I keep adding solution as it boils down after it gets pretty concentrated but still liquid, I pour off in bowl with lid, now cooling most of it crystalizes, I let it settle pour off concentrated liquid back to coffee pot, rinse crystals in sulfuric acid and put them in plastic container, sit them with lid loose by the wood stove to finish drying. this is not much trouble for me as most of this process does not need attention, and can be working while I am doing other things. and I have a good quality precipitant.

edit water does freeze out of the dilute acid (then Ill add lil more acid ) to bucket seems to help by raising specific gravity, and doesnt seem to hurt process, crock pot would also work (but mine are always full of crystalizing other acids to salts)

 

[allanwcoty]

First batch with the phone pieces & 10 cups new battery acid has a slight blue grean color with blackish remnants floating just off the bottom. Very little iron started this one.

2nd batch had 2 pads of laminae and 10 cups of new battery acid and has used it and another dose of about 2 cups and has used it but has not dissolved all the laminae. Coffeepot full of light blueish crystals and undissolved laminae.

Took several layers of the laminae from #2 and put in 8 cups of new battery acid and it dissolved leaving greenish liquid. Added several more laminae from #2 and now have greenish liquid and blueish crystals.

Butcher - Are you adding water just to get the acid to go further or is there another reason for the water?

Are there any problems with not burning off the laminae or from not seperating them (except for having an overabundance of product)? I have a coffeepot and a half at this point and thats just from several layers of the laminae.

Any other uses for the "copperas"?

Have a Happy and Safe New Year, allan

 

[Anonymous]

The gas would be for the most part hydrogen since the iron is replacing it in the solution.
Jim

 

[butcher]

ferrous sulfate FeSO4*7H20,
water is an ingrediant as far as I am concerned, I start off stronger but add water after it liquid starts turning blueish, I am not sure about this reaction but many metals will actually disolve better in dilute acids, and since sulfuric can be concentrated in Iron vessels (Cast Iron with silicon content) and dilute acid attacks them more than the concentrated acid,so this was my reasoning for the water addition, all I know this really makes nice ferrous crystals for me, and can use without crystalizing, i make the crystals for storage or for testing with. I have had jar of ferrous with Iron in bottom freeze the water (low acid and specific gravity) just adding a little more sulfuric acid will thaw and keep ice from forming Hydrogen bubbles , also if letting a solution sit for several days the hydrogen reacting with Iron the hydrogen gasses out, lowering acid content, adding a few drops of acid every once in a while is important to keep slightly acidic solution.
we have two chemists on the sight maybe one of them will get interested in this and give us a few more things to ponder.

 

[LittleJohnnyH2SO4]

Ill give a very quick explanaton of oxidation and reduction here. Oxidation is a loss of electrons (which have a -1 charge), while reduction is a gaining of electrons.

sulfuric acid is H2SO4. In water, it breaks up into 2 H(+1) ions and an SO4(-2) ion. H(+1) is a decent oxidizing agent. It accepts electrons from iron metal (which has a charge of 0) to make ferrous ions, which have a charge of (+2). By accepting the electrons, 2 H(+1) ions become H2, which is hydrogen gas and has a charge of 0.

Net reaction:

2H(+1) + Fe(0) --> H2(0) + Fe(+2)

H(+1) can't oxidize Fe(+2) any more, but the oxygen gas in air can like this:

O2(0) + 4Fe(+2) --> 2O(-2) + 4Fe(+3)

Fe(+3) is called a ferric ion. As long as there is extra acid in solution, it can dissolve. If there isn't any, your solution will start to get rusty looking, as will exposed crystals of ferrous sulfate. Ferric ion is useless for reducing gold to the metal, which relies on gold(+3) (auric ion) as an oxidizing agent like this:

Au(+3) + 3Fe(+2) --> Au(0) + 3Fe(+3)

The only thing that matters at all is the Fe(+2) being around. You're used to seeing copperas as the heptahydrate, which are the green-blue crystals, but the white powder is just a different hydrate missing a few water molecules. It will perform just as well as the green stuff at reducing your gold.

Any air oxidation of the ferrous ion is reversible as long as there is iron metal and acid left like this:

Fe(0) + 2Fe(+3) --> 3Fe(+2)

The black grunge at the bottom is probably traces of carbon powder and silicon powder from the iron. Gases coming off are almost entirely hydrogen and may have very, very small amounts of silane.

 

[butcher]

Thanks Johnny , I have a question here, maybe I am just confused here, I knew rust can be converted back to Iron metal with electrolisis(pushing electrons), I have used electrolisis to restore rusted antiques,but are you saying it can be done in just a chemical process? looks from equation rust and ferric sulfate converts to ferrous sulfate as long as hydrogen from acid present,if we gained two electrons we would be back to Iron, wouldn't this just be powder? and the electrical current needed for restoring rusted Iron antiques?
sorry if this is hard to understand I have a hard time saying what I mean.
and I am very new to chemistry trying to learn on my own.

Any air oxidation of the ferrous ion is reversible as long as there is iron metal and acid left like this:

Fe(0) + 2Fe(+3) --> 3Fe(+2)

 

[maynman1751]

Sorry for digging up a very old post buutttt. I am trying to make some ferrous sulfate. I'm using transformer laminates that I burned the impurities off. I'm using sulfuric drain cleaner 98% and diluting it with water 50/50.
AS soon as the reaction starts the solution turns a deep brown color. I've tried two different transfomer plates and diluting the acid further. I've done this before and everything went fine. Any ideas or will this still filter out OK. I certainly don't want ferric sulfate. I'm also using low heat.

 

[anachronism]

No disrespect but you can buy it cheaper than you can make it.

And it's pure 8) 8)

 

[butcher]

The sulfuric acid should be diluted to around 10% H2SO4 concentration.

 

[maynman1751]

No disrespect but you can buy it cheaper than you can make it.

And it's pure 8) 8)

Maybe, I don't know. I just like making my own.

 

[maynman1751]

The sulfuric acid should be diluted to around 10% H2SO4 concentration.

I have since diluted it considerably. Is this batch ruined or is it still salvageable Thanks!?

 

[butcher]

You may have iron in various oxidation states, (the reddish or brown sounds like rust) which may be insoluble in the solution...

Iron will passivate in concentrated sulfuric acid.

Iron will dissolve easier in the very dilute acid.

Oxygen in solution or iron exposed to air can also form iron in other oxidation states...

 

[Geo]

Iron oxide will dissolve into sulfuric acid easily. I doubt it's iron oxide. Drain opener has inhibitors but I have used it before myself with no issues. It may be the laminates. I found some time ago that some transformer laminates contain nickel. There may be other metals at play. When I make copperas, I use rusty nails. I actually use old pallets as wood for fuel in my incinerator. The nails left behind oxidize rapidly even if they are kept dry. I just toss a hand full in a 2000 ml beaker with 100 ml's of sulfuric acid and 900 ml's of water. Add heat all day and keep topping the solution up with water. There is quite a bit of carbon in steel and will form a black powder that has to be filtered out.

 

[maynman1751]

As usual a big Thank You to Richard and Geo! I split the solution, diluted it further and it just took off. Today I have a nice pale green solution that is growing beautiful green crystals.
Since my wife was paralyzed in a neck surgery in 2014 I'm pretty much on a hiatus from refining. Forgot some of the details but it's coming back. I'm starting to 'play' around with it again on a very limited basis.
So, Thanks again guys! John.

 

[butcher]

John, Some details may get foggy, as you get back into the groove they will become clearer again.

 

[solarnevo1]

Try this looks easy...
https://m.youtube.com/watch?v=sADtR1ytkwc