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Author: Subject: The lead salts preparation thread!
njl
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[*] posted on 22-9-2020 at 04:51


Can't find any refs for this but quick thought: Lead Boride by fusion of molten lead with stoichiometric elemental boron?
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Fyndium
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[*] posted on 8-10-2020 at 12:11


I put lead acetate on process about ½years ago.

It was prepared by making calcium acetate first, then reacting it with calcium sulfate, and then applying the clarified solution with lead shots. It sat about half a year, until the blue hue had disappeared and turned into greenish-brown.

The solution was decanted, and it was concentrated to about 1/8 of it's volume, and batches of crystals were obtained in two phases by cooling, precipitating and reconcentrating. A recrystallization was performed by dissolving the acetate in 1/2 of weight of water and heating until dissolved, and then cooling it down and finally cooling the solution with ice bath and the crystals were filtered.

A third recrystallization is required if pure white crystals are wanted, the dual rec ones are a bit yellowish.

Total yield to be measured, but it appears to be much lower than in theory.
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Fyndium
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[*] posted on 10-10-2020 at 11:54


I prepared and recrystallized the double displacement reaction produce.

The initial concentrate from the metathesis was just plain chunky black syrup. It was first suctioned dry from any residual water, and then dissolved in hot water and was left for crystallize and finally put into ice.

pb-rec1-2.jpg - 463kB

First recrystallization did bring out the yellow-brownish crystals. I did not actually take a picture from the mother liquor.

P.S. Piranha solution cleaned the clogged brown-gunk-impinged frit filter to a perfect condition.

pb-rec1-1.jpg - 155kB

After second recrystallization it was already much more pure.

The third recrystallization was enough to finalize the process, and shiny, white crystals were a result. No pics from third rec as well, because I accidentally deleted the pics.

pb-rec-final.jpg - 247kB

I also made a second batch just for fun from reagent grade GAA and PbO. The reaction kinetics were PITA, but it resulted in a crystal clear solution, which is left for crystallize.

crater1.jpg - 180kB

The solution apparently did not want to crystallize on it's own, so a seed crystal was dropped and then it turned into ice within a minute and heated up quite a lot.

I uploaded a little clip of the seeding.

https://vimeo.com/466935179
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Fyndium
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[*] posted on 20-2-2021 at 04:46


I have a few kg of lead sulfate crap from a battery. Was wondering if I could convert it into plumbite boiling with NaOH and then precipitate carbonate with bicarb?
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[*] posted on 20-2-2021 at 08:27


It can be directly converted by heating with Na2CO3 solution - PbCO3 is less soluble than PbSO4.



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[*] posted on 20-2-2021 at 08:43


That's quite true. I wonder how the conversion can be confirmed? Also, if the mix is very impure, it would be beneficial to be able to filter it, as plumbate should be soluble?
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[*] posted on 20-2-2021 at 09:33


Yes, plumbites are soluble.



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