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White Yeti
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Quote: Originally posted by blogfast25  | | That sounds very interesting, WY, but are you sure it was Fe2(CO3)3? Not some basic carbonate or even plain Fe2O3? Ferric acetate is an interesting
compound in its own right, so I might try that. Whether or not a carbonate forms with bicarbonate depends on the relative solubilities of ferric
hydroxide and ferric (basic?) carbonate... |
I tested the iron carbonate by dropping some of it into some lemon juice. As a control, I took iron oxide and dropped it into a separate container
with lemon juice. The carbonate started fizzing and the oxide did nothing at all. Afterwards, the carbonate turned the lemon juice into this red brown
liquid that remained brown after filtering, indicating the presence of iron(III) in solution.
I'm pretty sure I made iron carbonate, but I might be wrong. It's possible that I made a mixture of three separate compounds FeCO3, Fe2O3 and
Fe2(CO3)3, instead of just Fe2(CO3)3.
You can duplicate the procedure and prove me wrong
"Ja, Kalzium, das ist alles!" -Otto Loewi
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seashell1982
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Was there ever any consensus as to what this reaction produced?
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Perdurabo
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See Patent US 4657752
. . to make ferrous carbonate. Uses FeCl2 and NaHCO3; claims high purity. Though this is Iron(II) and not Iron(III) carbonate
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Poppy
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What about careful decarboxylation of Iron citrate?
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Poppy
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Here are the pictures of the decarboxilation at 280°C of iron citrate I performed.
Its considerably paramagnetic, as evidenced by small ammounts of it sticking to a neodimium magnet.
It has a very distinctive odour identical to that of oil paint.
Iron carbonate is evidenced to be present as it weakly fizzles when added to acidic aqueous solution.
The reaction is odd, never heard of anything similar, guess it can be washed with a proper organic solvent to remove the soot chains or whatever it is
sticking to the iron carbonate.
The reaction between Fe and citric acid was carried with iron III hydroxide, as it is easily soluble in acid, otherwise iron oxide didn't work for
this.
The intentional reaction was
C3H5O(COO)3(3-)Fe --> heat --> FeCO3 + CO2 + 2H2O + 4C + H
Please see http://www.nature.com/nature/journal/v179/n4562/abs/179733a0...
[Edited on 9-20-2012 by Poppy]
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plante1999
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| Quote: Originally posted by Poppy | Here are the pictures of the decarboxilation at 280°C of iron citrate I performed.
Its considerably paramagnetic, as evidenced by small ammounts of it sticking to a neodimium magnet.
It has a very distinctive odour identical to that of oil paint.
Iron carbonate is evidenced to be present as it weakly fizzles when added to acidic aqueous solution.
The reaction is odd, never heard of anything similar, guess it can be washed with a proper organic solvent to remove the soot chains or whatever it is
sticking to the iron carbonate.
The reaction between Fe and citric acid was carried with iron III hydroxide, as it is easily soluble in acid, otherwise iron oxide didn't work for
this.
The intentional reaction was
C3H5O(COO)3(3-)Fe --> heat --> FeCO3 + CO2 + 2H2O + 4C + H
Please see http://www.nature.com/nature/journal/v179/n4562/abs/179733a0...
[Edited on 9-20-2012 by Poppy] |
Your equation isn't properly balanced, there is only one ''atomic'' hydrogen in the product, please re balance it correctly so others can have a
better idea of the reaction intended.
I never asked for this.
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Poppy
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My mistake!
Sorry for such incovenience also the iron II product is not even wanted, and I don't think it would form at an oxygen atmosphere at all!
Proper balance with additional oxygen source gives now the suspected reaction below.
About 30g citric acid where used to prepare this, to say, 0.156 mol citric acid put to react with an excess of iron III hydroxide aqueous gel and
heated, finally comprising a 500mL solution.
Unreacted iron III oxide/hydroxide was filtered off, and probably has let iron make its path into oxides. I wouldn't admit a stoichometric reaction
anyway.
Well, 0.156 mol Iron III hydroxide is 25g, which sums up up the citric acid to produce theoretically about 47g of anhydrous iron III citrate.
The measured mass of the decarboxylated product was 20g.
Considering the experimental yield to be 50 percent, thats roughly correct an assumption:
2 FeC6H5O7 + 13,5 O2 --> Fe2(CO3)3 + 9CO2 + 14H2O
It also agrees with the observation of the product being very fluffly and of a very low specific gravity, implying a lot of components must have
escaped as gases. The oxydation was self catalysed by iron.
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blogfast25
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You have a lot more work to do before you can confidently claim you've synthesised ferric carbonate. For example, on calcining, what's the weight
loss? Or by treatment with dilute strong acid how much CO2 do you get per gram of product? Are these results consistent with Fe2(CO3)3? Or is it a
basic carbonate?
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Poppy
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I'm so excited about it. Verifying with CO2 release will be the ultimate test whatsoever.
Although it might be an easy route, its an expensive one, industrially.
Between if it is really the carbonate its worth consider the compound not so reactive as one would expect, alike Na2CO3.
I tested with nitric acid, which is not a good solvent for Fe or Fe2O3 anyway.
[Edited on 9-21-2012 by Poppy]
I did a preliminary test. I've put some of the powder into conc. hydrochloric acid, it fizzled, but such of a sort not much better than with nitric
acid. I did it with so little powder I don't think it would give good results at all.
Anyone who deal't with CaCO3 and acid could give a tip on how long it takes to dissolve? It could be that Fe2(CO3)3 takes even longer to dissolve.
Even if the reaction didn't proceed too well from the decarboxylation at first, I'd put a bet: longer and hotter deal in the oven could probably do
the job.
[Edited on 9-22-2012 by Poppy]
I came up the idea I'm pretty sure about : it may have become iron carbide thats why it doesn't reacts.
[Edited on 9-22-2012 by Poppy]
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blogfast25
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| Quote: Originally posted by Poppy |
Between if it is really the carbonate its worth consider the compound not so reactive as one would expect, alike Na2CO3.
[Edited on 9-21-2012 by Poppy]
Anyone who deal't with CaCO3 and acid could give a tip on how long it takes to dissolve? It could be that Fe2(CO3)3 takes even longer to dissolve.
I came up the idea I'm pretty sure about : it may have become iron carbide thats why it doesn't reacts.
[Edited on 9-22-2012 by Poppy] |
First point: various D-block element carbonates are all pretty reactive to acids.
Second point: how long it takes to dissolve depends on soooo many factors. But there’s no a priori reason why ferric carbonate would not react
vigorously with dilute acids.
Third point: pray, tell, how?
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