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Sulaiman
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not quite as hoped
I decided to recover lead from two vrla batteries.
I tried a few rotary power tools but they snatch too easily
A small hand axe / hatchet placed on the seam
hit with a lump hammer / mallet opens up everything in seconds with little mess or danger.
Each cell had four plates in shiny condition.
From those I got 1.4 kg of lead
(commonly alloyed with antimony, calcium or other secret recipe ingredients)
the rest of the battery contents were VERY corroded plates, various small pieces of lead, lead dioxide and fibers.
I removed most of the fibrous material and put the rest in a pot and cooked it to get more lead.
Result : the lead dioxide decomposed to lead oxide,
releasing lots of oxygen,
which converted almost all of the lead to lead oxide 
not exactly what I expected.
this is the pot of cooked stuff
the matchstick-like pieces were lead metal
on the left is a solder pot for making a nice pill-shaped lump of any recovered lead

this is one of the sticks broken in half
not much lead left in there.

So other than carbothermal reduction (lead in vapour phase = no thank you)
is there a simple cheap way to reduce the oxide ?
a slightly clearer view of the cooked contents
CAUTION : Hobby Chemist, not Professional or even Amateur
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Sulaiman
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(stainless steel pot) + (oxygen) + (heat) =

It does not matter because it was ex-kitchen,
but I fancy cleaning it up anyway.
I have some potentially relevant acids in stock:
oxalic, citric, acetic and hydrochloric.
I've previously used a mixture of oxalic and citric acids for successfully cleaning stainless steel,
but not with this much corrosion.
any suggestions ?
[Edited on 1-1-2025 by Sulaiman]
CAUTION : Hobby Chemist, not Professional or even Amateur
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bnull
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Mood: Sneezing like there's no tomorrow. Stupid cat allergy.
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First step: an alkaline bath to dissolve some of the polymerized oil. Sodium hydroxide with a little detergent is fine. You may prefer to leave it
steeping in hydroxide at room temperature until most of the polygunk has softened or dissolved, or for 4 days to be on the safe side.
Second step: a nice rubbing with a wire brush to remove the most stubborn flecks of polygunk. It is not necessary to make it shiny again.
Third step: acid bath. I have used citric acid, hydrochloric acid, a mixture of citric and hydrochloric acid (who knows why), acetic acid, and oxalic
acid. The winner was oxalic acid. The only downside is that you need to brush it occasionally to remove any adhering oxalate, especially when the
surface is pitted. Hydrochloric acid is too corrosive for me and tends to make a mist. Acetic acid sort of stinks. A mixture of citric and oxalic
acids will do. But you need to remove the polygunk first.
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chloric1
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Mood: Stoichiometrically Balanced
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Made about and ounce of barium bromide but was expecting more, oh well. The barium carbonate I started with was technical grade so I used a slight
excess and converted barium waste to chloride first then to barium sulfate with Epsom salts. It’s white so I assume it’s sulfur free but I may
have barium thiosulfate as an impurity so I have a waste jar with barium sulfate milk in it. When I get 100 grams of barium sulfate, I’ll try to
carbothermic reduction to barium sulfide. Any barium sulfate that doesn’t react, I’ll have a separate jar for “black ash barium”
Also make a few tens of grams of ammonium nitrate from isolating waste nitric acid by distillation. The nitric acid obtained was rather weak so I
just poured ammonia into it until pH 7. Slight excess
Fellow molecular manipulator
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Sulaiman
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result of inaction....
while deciding what to do with my pot I left it by a sink,
where it was exposed to rainwater and indirect sunlight

I have often caused mild corrosion to stainless steel
I've previously only once significantly corroded stainless steel
by pouring molten iodine into a stainless steel cup
similar to the one coincidentally in the photo.
I am amazed at this level of corrosion.
I am now in the process of moving to a hopefully permanent address
so I will pass the problem of my corroded pot and battery waste to a landfill :(
FAIL
A terrible negative for my 'green' initiative.
CAUTION : Hobby Chemist, not Professional or even Amateur
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Rainwater
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By absorbing oxygen from the air as well as a variety of pollution, i tent to have that effect.
Re pickeling the pot with dilute nitric acid should rebuild the chrome oxide coating that prevents rust and keeps you looking shiny
"You can't do that" - challenge accepted
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j_sum1
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Iodometric titration of hypochlorite.
I picked up a 20L drum of "pool chlorine" for a good price a while back. I just put a couple of litres in the fridge preparing for some chloroform. I
figured it was sensible to check concentration first.
Alas, my titration is not working. I think I am a factor of 10 off in one of my calculations and solution preps. I have spent the last hour chasing
decimal points and can't find my error.
Time for an afternoon movie. I will get back to it later.
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j_sum1
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I had a foil bag of ferric nitrate nonahydrate, which, typical of nitrates, was effective in destroying its container.
Production of nitric acid proved to be a really straightforward and simple process. Quick distillation, no foaming, good yield, no mess.
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