hadiish
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Rare earth nitrate
Hi ^_^
I want to preparation rare earth nitrate <M(NO3)3> from theirs oxides such as Nd2O3 , Gd2O3, Tm2O3
I know I must use HNO3 for this
but I don't know about the experimental method  and can not find the explained
method for this
they aren't complete:
ex:
<< In the next step, the residue is dissolved in hot nitric acid concentrate and a nitrate rare earth solution was obtained which can be shown
through the reaction (2) bellow:
Ln2O3 + 6HNO3 → 2Ln(NO3)3+ 3H2O (2)
In order to avoid the loss of acid vapors a Graham condenser with reflux was installed at the upper side of the Erlenmeyer>>
any one can help me for solve my problem ? ^_^
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LanthanumK
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NurdRage has an excellent video on how to prepare two rare earth nitrates: http://www.youtube.com/watch?v=8IFsOmriS8I
hibernating...
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blogfast25
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Your rare earth oxides (a long time ago these would literally be called ‘Rare Earths’, ‘earth’ back then being the mundane term for
‘oxide’!) may or may not dissolve easily in strong HNO3 or even concentrated HNO3. That will depend on the degree of calcination they suffered
during their production. Heavily calcined ‘earths’ may need dissolving in conc. H2SO4, fused with NaHSO4 or boiled in conc. H2SO4 + ammonium
sulphate. Then dilute and neutralise the solution as fresh, precipitated hydroxide (RE(OH)3), wash carefully and plentifully and dissolve in the
requisite amount of HNO3…
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hadiish
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Quote: Originally posted by blogfast25  | | Your rare earth oxides (a long time ago these would literally be called ‘Rare Earths’, ‘earth’ back then being the mundane term for
‘oxide’!) may or may not dissolve easily in strong HNO3 or even concentrated HNO3. That will depend on the degree of calcination they suffered
during their production. Heavily calcined ‘earths’ may need dissolving in conc. H2SO4, fused with NaHSO4 or boiled in conc. H2SO4 + ammonium
sulphate. Then dilute and neutralise the solution as fresh, precipitated hydroxide (RE(OH)3), wash carefully and plentifully and dissolve in the
requisite amount of HNO3… |
you said I must prepared Re(OH)3 firstly then I must prepared Re(NO3)3 from this ?
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not_important
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Yes, if the oxides turn out to be non-reactive to HNO3. As blogfast25 stated, the lanthinide oxides vary in their reactivity depending on their
thermal history and other generally physical factors. If a small amount of the oxide will not dissolve in 75% or so HNO3, then you must react it with
hot concentrated H2SO4, or fuse with NaHSO4, or some other process, prepare the hydroxide from that, then dissolve in in HNo3 (again, as blogfast25
said).
Note that nitrates prepared using HNo3 will be hydrated forms, it's more complicated to get the anhydrous nitrates.
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blogfast25
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An alternative route would be to obtain the hydroxide (by the methods described) and convert it to fluoride. NdF3 for instance is water insoluble and
could probably be obtained by (assuming the fluoride is more insoluble than the hydroxide):
Nd(OH)3(s) + 3/2 NH4HF2(aq) === > NdF3(s) + 3/2 NH3(aq, g) + 3 H2O(l)
The (dry!) fluoride can then be reacted with Mg powder:
NdF3 + 3/2 Mg === > Nd + 3/2 MgF2
So the metal is obtained. The reactive RE should dissolve swiftly in dilute HNO3, to obtain the hydrated nitrate.
It’s a lot more adventurous, you get to obtain the metal but it takes more expertise to pull it off…
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