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Author: Subject: The lead salts preparation thread!
12AX7
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[*] posted on 10-12-2006 at 19:00


I have a solution of mildly acidic (about equal to that from hydrolysis, it's not too stinky) lead acetate drying as we speak. It has little scum in it, last I checked.

Tim




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[*] posted on 11-12-2006 at 06:48


what about your PbO? is it pure or technical? I think the problems always in lead raw like PbO, Pb3O4, and lead alloy? you can prepare pure Lead acetate in simple method:

1) purification your lead alloy (more the 90%Pb) by electrolysis solution, I tried with diluted HCl and it give good results, you will get fine powder with high current "I think there are better bath for purification of lead".
2) wash your powder with distilled water and then put it in acetic acid for 24 hours, you will get clear solution with some ppt filter it and recrystalize your salt by heat at 80-100 to prevent any oxidation of acetate, cool and collect your crystals.
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12AX7
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[*] posted on 11-1-2007 at 18:35


The most beautiful lead acetate crystals yet.

Chem_PbAc22.jpg - 43kB




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[*] posted on 13-1-2007 at 22:07


AAAAUUG! I think this should be said.....For a pro chemist I don't suppose this is a problem, but for beginners at home.....

The toxicity of lead is greatly underestimated by the general public! And greatly understated in chemistry books. I had lead poisoning when I was 8 or so from lead dust from battery terminals, and lead paint, and my dad *is a chemist*. IT IS BAAAAAADDDDDDDD!!!! He still doesn't believe it's seriously poisonous, inexcusably stupid..... But just because it's LD50 is high, doesn't mean it can't cause devastation at very low doses. You don't even notice you're getting poisoned, it's kind of like being sleep deprived all the time (but much worse), instead....

Check it out, the max. intake per day is only a few *micro*grams.
And for young-uns it should absolutely be banished from their environment. There's no way you can practicaly handle it in a safe fashion.
These pages are mostly about lead paint, but obviously it applies to other lead sources too.....

http://www.nsc.org/library/facts/lead.htm
http://www.niehs.nih.gov/oc/factsheets/lyh/govtdo.htm
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[*] posted on 20-1-2007 at 14:57


I have some Lead and vinegar in a beaker, its turned orange. Same thing happened when I heated a sodium acetate solution. What happened?

[Edited on 1/20/2007 by guy]




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[*] posted on 20-1-2007 at 15:43


Sorry to be slightly off topic, but does anyone have ANY info on lead oxalate? I can find absolutely nothing on the internet. I'm looking mostly for its bp/decomp temp.



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[*] posted on 11-3-2007 at 16:16
Instant white precipatate(Lead Acetate)


While setting up the necessities to make lead acetate, I decided to pour the acetic acid on while still boiling. Immediately, a large amount of white precipitate formed and settled all over the lead like the aftermath of a snow storm.

Any ideas what this stuff is ?
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[*] posted on 11-3-2007 at 16:29


Quote:
Originally posted by UnintentionalChaos
Sorry to be slightly off topic, but does anyone have ANY info on lead oxalate? I can find absolutely nothing on the internet. I'm looking mostly for its bp/decomp temp.


Sol. 0,15 mg/100ml @ 18 C
sp. gr. 5,28
decomposes circa 300 C
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[*] posted on 19-3-2007 at 13:39


Quote:
Originally posted by guy
I have some Lead and vinegar in a beaker, its turned orange. Same thing happened when I heated a sodium acetate solution. What happened?

[Edited on 1/20/2007 by guy]


Was your NaOAc made using vinegar?

Lead acetate can form colored complexes with some of the flavonoids & other impurities of natural products (presumably, this includes vinegar). Even though vinegar is said to be distilled, some impurities will have come over if it wasn't done via sub-boiling distillation.

Now, if you didn't have transition metal impurities in your NaOAc and it still turned orange, not sure what it could be. The pure ones shouldn't turn color though.

What kind of container are you storing your vinegar in?
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[*] posted on 19-3-2007 at 13:58


Quote:
Originally posted by Pyridinium
Quote:
Originally posted by guy
I have some Lead and vinegar in a beaker, its turned orange. Same thing happened when I heated a sodium acetate solution. What happened?

[Edited on 1/20/2007 by guy]


Was your NaOAc made using vinegar?

Lead acetate can form colored complexes with some of the flavonoids & other impurities of natural products (presumably, this includes vinegar). Even though vinegar is said to be distilled, some impurities will have come over if it wasn't done via sub-boiling distillation.

Now, if you didn't have transition metal impurities in your NaOAc and it still turned orange, not sure what it could be. The pure ones shouldn't turn color though.

What kind of container are you storing your vinegar in?


I bought it in the plastic container. I think it may have "carmelized" or something like that. It only turns to brown when it becomes really concentrated. Maybe as it evaporates NaOH accumulates an may cause some carmelizing.
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[*] posted on 9-5-2007 at 10:23
PbO from Alkali metal nitrate and Lead metal


Hello,

Can PbO be made in a straight forward manner from Sodium Nitrate + Lead Metal.
Sodium Nitrite being the biproduct.

Dann2
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[*] posted on 9-5-2007 at 10:40


Yes, I believe it can.

When I used to make NaNO2 using raw lead and NaNO3 there was always a lot of orange precipitate formed as byproduct. I'm sure this was PbO as it looked just like the PbO that I had bought.




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[*] posted on 9-5-2007 at 10:55


Also, electrolyzing lead electrodes in ammonium nitrate solution is supposed to to work...

[Edited on 5-9-2007 by Eclectic]
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[*] posted on 9-5-2007 at 11:10


I tried the Ammonium Nitrate + Lead anodes and Cathodes.
There was alot of Spongy Lead forming.

With the Lead Metal + Nitrate what do I do?
Dissolve the (Na) Nitrate in water and add Lead and Heat?

Would Ammonium Nitrate do.

TIA.

Dann2
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[*] posted on 9-5-2007 at 11:36


You have to use molten NaNO3.

You didn't get lead hydroxide/oxide as the electrolysis proceded? I thought H2 was evolved and lead hydroxide/oxide precipitated.

12AX7 says NaNO3, NaClO3, or NaClO4 work as electrolytes.

Ah Ha! I bet the ammonium nitrate solution solubilizes the lead hydroxide, just like it does lead chloride.

[Edited on 5-9-2007 by Eclectic]
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[*] posted on 9-5-2007 at 12:05


Quote:
Originally posted by Eclectic
You have to use molten NaNO3.

You didn't get lead hydroxide/oxide as the electrolysis proceded? I thought H2 was evolved and lead hydroxide/oxide precipitated.

12AX7 says NaNO3, NaClO3, or NaClO4 work as electrolytes.

Ah Ha! I bet the ammonium nitrate solution solubilizes the lead hydroxide, just like it does lead chloride.

[Edited on 5-9-2007 by Eclectic]


I did get a white precipitate coming on the anode. The anode needed cleaning every half hour or so. If it was not cleaned Lead Dioxide started to form on it. (Thats what it looked like). Spongy lead was forming on the Cathode. The whole thing was rather messy.
Would a diaphram help?

Will try the Na Nitrate + Lead for litharge.#

Cheers,

DANN2
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[*] posted on 9-5-2007 at 12:21


Alkaline conditions at the cathode precipitate PbOH2, acidic conditions at the anode dissolve Pb, so I think a diaphragm might hurt rather than help. Na salt electrolytes would probably work better. Maybe fiddle with cell conditions so lead does not plate out, use AC, stirring?

Stirred molten lead and NaNO3 melt is a mess too...
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[*] posted on 9-5-2007 at 17:55


Quote:
Originally posted by Eclectic
Alkaline conditions at the cathode precipitate PbOH2, acidic conditions at the anode dissolve Pb, so I think a diaphragm might hurt rather than help. Na salt electrolytes would probably work better. Maybe fiddle with cell conditions so lead does not plate out, use AC, stirring?

Stirred molten lead and NaNO3 melt is a mess too...


Thanks for reply,

Will the lead ions and the OH ions not meet at the diaphram and react there (precipitate Lead Hydroxide) and therefor keep the anode free from hydroxide ppt.

I have been doing some reading from here:

http://www.sciencemadness.org/library/books/the_manufacture_...

Alkali conditions at the cathode due to formation of some ammonia cause Plumbites to form. The plumbites then cause spongy lead to deposit. page 45 (I am not up to speed on the chemistry myself).


Will persevere.

Dann2
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[*] posted on 9-5-2007 at 18:14


Sounds like it's best to avoid ammonium and nitrate altogether and use bicarb and sodium chlorate. See page 42-43.
Thanks for the reference, as I couldn't recall where I had seen ammonium nitrate used. :(

I think the PbOH2 might clog up the pores in a diaphragm.

[Edited on 5-10-2007 by Eclectic]
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[*] posted on 10-5-2007 at 17:44


Hello,


I obtained another patent US563,555 Manufacture of White Lead.

__________________
A cell with two diaphrams is used.
Alkali Metal Nitrate is used. So can acetate.
Concentration not stated.
Anode in one compartment is Lead.
Cathode in another compartement is copper.
Third compartement is in the middle.
As the cell is operated liquid is drawn from Anode
compartement and the middle compartement and mixed outside the cell.
Lead Hydroxide precipitates and the liquid is returned to cell.
Current density on anode is 15.5mA per square cm.

(The hydroxide is then converted to Basic carbonate by air.)
____________________________________________-

Tim Williams suggested that Perchlorate would be better
than Nitrate or Chlorate as it is harder to reduce (at cathode) and therefor you will get less Lead Metal forming on the Cathode.

To work a cell with no diaphram you would need a mechanical moving brush set up to keep the hydroxide off of the Anode. (or sit there yourself wipeing (and weeping!))
IMHO.

I attempted to make Litharge from Sodium Nitrate + Lead.
First attempt I used Stiochiometric amounts and got lots of Lead Metal.:D
Next time I kept adding the Nitrate to the molten Lead untill I reckoned all metal was gone.
It seems easy enough.

What will happen if I heat too much.

Dann2
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[*] posted on 11-5-2007 at 13:02


Quote:
Originally posted by dann2
Hello,

Can PbO be made in a straight forward manner from Sodium Nitrate + Lead Metal.
Sodium Nitrite being the biproduct.

Dann2


Can one make the reaction with tin?

NaNO3 + Sn => NaNO3 + SnO
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[*] posted on 11-5-2007 at 13:55


It probably goes to SnO2. I don't know if NO2- would be reduced further, or if transient species like nitrogen atoms would be oxidized to nitrite by the SnO2.

Tim




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[*] posted on 13-5-2007 at 05:49


Hello,

Finished my second attempt at making PbO using
Lead Metal and Na Nitrate. I stirred and stirred adding
Na Nitate untill I was sure that all the Lead was gone.
I washed but there was still quite alot of Lead Metal
still not reacted.
I presume that alot of the Oxygen is escaping.

It least the ingredients are cheap and the products easy to seperate.

PS: It's a bit messier than I originally thought :-|

Is there anything I could add to catalize the reaction??

DANN2
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[*] posted on 13-5-2007 at 06:18


The reactions going on are

2 NaNO3 => 2NaNO2 + O2
Pb + NaNO3 => NaNo2 + PbO
2Pb + 4NaNO3 => Pb3O4 + 4NaNO2

The reactions with lead are exothermic and run fast, not catalysis is needed, nor do I know of any. As lead is much denser that the sodium compounds, it is better to add the lead in a somewhat divided or thin sheet form to the molten sodium nitrate. Your stirring needs to kick up any lead at the bottom of the container, an inverted T shape that sweeps across the bottom should work OK.

If you're not after the NaNO2, it might be better to just heat the lead in air at slightly above its melting point, skimming off the PbO whenever it gets thick enough.

And if it's lead salts you're after, the lead-acetic acid-air route works OK, just keep it running until everything has dissolved.
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[*] posted on 13-5-2007 at 11:51


I never got good results, hell any results, from stirring hot lead. The process makes a green granular substance that turns out to be lead spheroids with little oxide on top. Also little weight gain.

Tim




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