Iron(II) chloride to Iron(II) sulfate

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Geo

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Is it possible to react ferrous chloride with sulfuric acid to make ferrous sulfate. I've been thinking of trying it to see if I can make blue copperas crystals using ferrous chloride. I am not very good with chemistry and I'm sure I could find this own my own but I'm also sure there are so many on here that may be willing to give me a hand with it, I hope. :lol:
 
I shouldn't reply as I'm not that good at it, but I'll give it a shot.

Initially I thought about oxidizing the chloride and then let it dissolve in sulfuric, so I've searched for two set of keywords "ferrous/iron chloride to ferrous/iron oxide" and "ferrous/iron oxide to ferrous/iron sulfate" and I come up with with a couple of results:
http://www.google.com/patents/US2592580 said:
It has also been proposed to produce ferric oxide from ferrous chloride-containing solutions by evaporating such solutions to dryness and thereafter oxidizing the resulting ferrous chloride by means of air in the presence of water vapor. Such processes suffer from the drawback that the moist hydrochloric acid vapors formed during the oxidation reaction are very corrosive, attacking readily the metal parts of the apparatus with which they come into contact, unless expensive acid resistant materials are used in the construction of the apparatus employed.

And http://books.google.it/books?id=Owuv-c9L_IMC&pg=PA555&lpg=PA555&dq=iron+oxide+to+iron+sulfate&source=bl&ots=zXp_6meRld&sig=PdSnLi903VILKCHYoMuAHY9BmB8&hl=it&sa=X&ei=ViVWVIayMIiraarTgcgP&redir_esc=y to make sulfate from Iron(III) oxide.

The only doubt I have is if iron chloride would actually oxidise to (III)

Really hope it helps.
 
It's much easier to dissolve Iron in dilute H2SO4,as long as you keep it away from contact with Oxygen, otherwise it will Oxidize to Ferric and won't work as a reducing agent.
Actually, Ferrous Chloride might precipitate Gold. Never tried it, but it might work.

According to this, it does:

"Reducers precipitate gold from different solutions in divergent forms. Ferrous chloride and sulphate, arsenious acid, antimonious acid, and stannous chloride throw it down as a brown powder of varying degrees of subdivision, the precipitate with ferrous chloride being more finely divided when the gold solution is poured into the iron solution than that produced by the reverse method. The more dilute the gold solution, the finer is the subdivision of the precipitate. From concentrated solutions the metal often separates in lustrous laminae. A soft, yellow gold sponge is produced by addition of a small proportion of oxalic acid and a large proportion of potassium carbonate to a concentrated solution, the resulting mixture being then boiled with more oxalic acid."
http://gold.atomistry.com/extraction.html
 
Thanks MarcoP, and thank you Irons. Yes, dissolving the iron directly into diluted sulfuric is the norm, but occasionally, I like to try things just for the knowing. I know that adding sulfuric acid to some chlorides produce sulfates of those chlorides. It's usually an all day process to make a batch of ferrous sulfate. I can dissolve a few steel wool pads in HCl in a couple of hours tops. I am already pretty sure about the conversion of the chloride to sulfate but I would like either some confirmation on the feasibility of a quicker process or whether it's just not as good as direct dissolution in sulfuric acid. I can try it myself but I would hate to waste the materials on something that just wont work.
 
You can also add Iron to spent Ferric Chloride to reduce it back to Ferrous Chloride. You start out with Auric Chloride in HCl, add Ferrous Chloride to precipitate the Gold and filter, leaving you with a solution of Ferric Chloride in HCl. You add Iron in excess to convert the Ferric back to Ferrous and the HCl reacts with the excess Iron to give more Ferrous Chloride.

Having excess Iron will also reduce a lot of other contaminant elements and precipitate them out, but it would have to be filtered anyway before reuse.
 
The chloride is more volatile than the sulfate.

If you have a solution of iron chloride, you can add sulfuric acid and heat the solution to drive off the more volatile chlorides as vapors with an evaporation process.

(these can also be distilled out of solution, to save some of the HCl, by bubbling the volatile gas into a cold jar (a jar sitting in ice or snow) with a little water in the jar for the gases bubbling into the cold water to dissolve the HCl gas into to make HCl acid).

The iron will take on the sulfate leaving you with a ferrous sulfate solution, this may need crystalized a couple of times to get a more pure copperas crystals.

Note with too strong of heating you may get some hydroxides or oxides of iron (red rust), just do not heat the solution too strongly, there is no reason to boil the solution...
 
I have used ferric chloride to precipitate my gold (pictured)

Because the jug is marked ferric not ferrous I assume it is the iron (III) chloride & not the iron (II) chloride

From wiki; - ferric (iron III) chloride http://en.wikipedia.org/wiki/Iron(III)_chloride {Edit Nov. 4/14 --- link not working right - not sure what's going on here}

From wiki; - ferrous (iron II) chloride http://en.wikipedia.org/wiki/Iron(II)_chloride {Edit Nov. 4/14 --- link not working right - not sure what's going on here}

so I believe it is the ferric that will precipitate gold but not the ferrous

Anhydrous iron(III) chloride may be prepared by union of the elements:[7]
2 Fe(s) + 3 Cl2(g) → 2 FeCl3(s)
Solutions of iron(III) chloride are produced industrially both from iron and from ore, in a closed-loop process.
1.Dissolving pure iron in a solution of iron(III) chloride Fe(s) + 2 FeCl3(aq) → 3 FeCl2(aq)
2.Dissolving iron ore in hydrochloric acid Fe3O4(s) + 8 HCl(aq) → FeCl2(aq) + 2 FeCl3(aq) + 4 H2O
3.Oxidation of iron (II) chloride with chlorine 2 FeCl2(aq) + Cl2(g) → 2 FeCl3(aq)
4.Oxidation of iron (II) chloride with oxygen FeCl2(aq) + ¼O2 + HCl → FeCl3(aq) + ½H2O
5.Reacting Iron with hydrochloric acid, then with hydrogen peroxide. The hydrogen peroxide is the catalyst in turning iron chloride into ferric chloride

Like many other hydrated metal chlorides, hydrated iron(III) chloride can be converted to the anhydrous salt by refluxing with thionyl chloride.[8] Conversion of the hydrate to anhydrous iron(III) chloride is not accomplished by heating, as HCl and iron oxychlorides are produced.

Hope that is of some help

Kurt

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You want to specifically use Fe(II) sulfate; not Fe(II) choride or halide.

Ferrous sulfate is oxidized by gold (III) to ferric sulfate, in the process, reducing your gold.

Copperas is quite cheap a chemical.


Lou
 
Lou said:
You want to specifically use Fe(II) sulfate; not Fe(II) choride or halide.

Ferrous sulfate is oxidized by gold (III) to ferric sulfate, in the process, reducing your gold.

Copperas is quite cheap a chemical.


Lou

This has been more of a theoretical discussion initiated by Geo. Agreed, FeSO4 is cheap and easier to find, but some of us like to experiment or find ways of recycling reagents or making them from alternate sources.
Who knows if Fe(II) Sulfate will be available after the Rapture. :mrgreen:
 
Irons said:
It's the Ferrous (Iron(II)) that is the reducing agent, not Iron(III).

Interesting - all I really know is that the jug (which is marked ferric - not ferrous) does work to precipitate gold - so because its marked ferric I "assume" its iron (III) & not iron (II)

I am not even really sure where I heard about using it anymore as it is something I bought back when I was first starting into this (which was like 6 or 8 months before I joined the forum)

after joining the forum I have been using SMB &/or oxalic acid & in the future intend to make my own ferrous sulfate per butcher's instructions

The jug of ferric chloride I pictured was put away along with a lot of other things after I first joined the forum & to be honest I had forgot about it until Geo posted this thread so went & dug it out - will have to try it again the next time I am working on gold

Also I just tried the links (to wiki) I provided in my other post & they seem to not work - not sure what's going on there

Kurt
 
kurtak said:
Also I just tried the links (to wiki) I provided in my other post & they seem to not work - not sure what's going on there

Kurt

Put URL tags around the link and it will work. The forum software does it's best to recognize links but sometimes it makes mistakes.
Code:
Compare - ferric (iron III) chloride   http://en.wikipedia.org/wiki/Iron(III)_chloride 
With - ferrous (iron II) chloride  [url]http://en.wikipedia.org/wiki/Iron(II)_chloride[/url]
Gives
Compare - ferric (iron III) chloride http://en.wikipedia.org/wiki/Iron(III)_chloride
With - ferrous (iron II) chloride http://en.wikipedia.org/wiki/Iron(II)_chloride

... and Dave beat me with seconds! :mrgreen:

/Göran
 
FYI:

FeCl2 can be made into FeSO4 by heating with sulfuric acid (distills off nasty HCl gas).
 
Thanks guys. I've been away from my computer for a couple of days. I was at one of our members house helping out with some refining tips. I went up Monday morning and am just getting back. He had some material that he just couldn't get straightened out. I really wished I had more time because he had some really great stuff. Doing small batches of material left in different stages of processing is a challenge. I did the hardest stuff first and still managed to get over twenty grams of gold out (my estimate).
 

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