Smelting lead oxide?

[Blackwater]

I have some lead that has been kept outside, exposed to the weather, and it has a significant amount of white powdery coating which I believe to be lead oxide. Is it safe to throw this metal into the smelting pot with the white powder on it, and melt it as is? I don't recollect this question being asked here, though it's possible I missed it.

[mpmarty]

place it in a cold pot and bring it up to temp gradually to boil off any residual moisture then you should be fine.

[Blackwater]

Moisture isn't a problem. It's the lead oxide, which is poisonous. Will it fume, or melt??? I have enough health problems without taking on any new and unnecessary ones.

[blaser.306]

As mentioned before , Start cold bring it up to temp and flux it like crazy . You should just re combine the lead oxide to the melt? As long as you do not stir the dust up into the air while doing it I would imagine you would be fine. I have a box of about 400 lbs of cupcake ingots in the same condition that I need to get done before the snow flies here . If we are around to read following posts I suspect that it all worked out !!!

[DLCTEX]

Melt em, flux em. cast em.

[Springfield]

Just don't get the white powder on your hands. I have been told that the oxide will be absorbed through your pores as it is a very fine dust.

[cbrick]

Lead doesn't absorb through the skin but the lead oxide is a fine dust and will be all over your hands. Then when you rub your eyes, eat, pick your nose or suck your thumb it will get into you. Lead has to be ingested to get into you. Wash your hands well before you do anything after handling especially oxidized lead.

Don't knock the ingots around before melting so you don't get any of the dust airborne, probably wouldn’t be much but it could be possible to breath it. It's not radioactive and cannot jump out and get you but good hygiene after handling is common sense.

I’ve handled a lot of oxidized lead and my blood lead level checks in the low range of normal adult every year.

Rick

[runfiverun]

i'd be very careful melting them and very wary of the moisture.
i bet you hear them sizzzle when melting them.
use carbon and fire and you'll get most all the oxides back.

[geargnasher]

+1 Rick and R5R!

A further note on "fluxing", you should add a few handfuls of sawdust and possibly a dose of candle wax to the smelting pot after you put the cold ingots in and turn on the heat. Once it starts to smoke, light the smoke if possible, or add a half-cup of diesel oil and light that. The smokey, low-oxygen, HIGH carbon monoxide layer this will create on top of the metal as it melts will actually chemically "reduce" the oxides to their elemental state, in other words it will UN-oxidize the oxides.

Carbon Monoxide wants to become carbon DI-oxide, and it will cause an electron transfer that takes an oxygen atom from the lead oxide. Carbon, created by the soot from poor combustion, will tend to form CO and then CO2 as it also gains oxygen atoms from the oxidized metal.

In the final smelting process of Galena (lead ore), the lead ore is exposed to a highly concentrated CO atmosphere in it's molten state, which induces the Reduction/Oxidation which converts lead oxide to elemental, metallic lead. You're basically reproducing this situation in your smelting pot, plus the sawdust actually "fluxes" by absorbing things boolit casters consider impurities (calcium, aluminum, etc.) into the ash where they can be removed.

Gear

[cbrick]

runfive is correct, I forgot to mention, once melted flux with sawdust stirring well and the oxides will return to the melt. The oxidized lead won't fume but will sit on top of the melt until fluxed.

Moisture could be trapped in the lead so the advice to not add ingots to the melt is wise. Start adding ingots to an emptied pot and by the time they melt any possible moisture will be gone.

Rick

[olafhardt]

One of the purposes of fluxing is that it converts lead oxide back to lead. Don't eat any of it.

[Beagler]

Just don't get the white powder on your hands. I have been told that the oxide will be absorbed through your pores as it is a very fine dust.
You have to eat it of breath it in. Trust me I know I'm around thousands of pounds of lead oxide everyday. And I'm talking the really good red/orange stuff. You will learn when you need to hold yer breath and when to where a respirator.

[Blackwater]

This is why I love this place. One decent question and there's answers from every rational point of view, and multiple posters with professional or other insightful depth of understanding check each other to ensure definitive answers. Thanks!

[geargnasher]

Things related to this hobby can kill you, seriously and permanently injure you, or make you ill. We certainly don't want an ounce of prevention to be missed if possible. Neither do we want old wive's tales pervading the hobby and complicating or unnecessarily limiting the efforts of our casting bretheren. I've gotten more excellent advice here than from years of reading publications on the subjects discussed here.

Gear

[44man]

Now let me see, how can I dispute Rick and Gear? Umm, seems I can't. :grin:
Of course I never can!
Lead is just not that dangerous, don't breath dust or eat lead. Wash your hands after.
Smelt outside with the wind at your back, maybe better from the side a little.

[mpmarty]

Until the lawyers got into the game there never were any lead warnings in the casting manuals. Safest way to smelt lead? Kill all the lawyers first.

[zxcvbob]

I save up my lead oxide (usually black, not white, I wonder if you have lead carbonate) and add a little stale cooking grease and spent tumbling media to it and cook the daylights out of it in a stainless steel pot with a lid. Most of it turns back into lead. I know it's not really worth the effort and the electricity it takes, but I feel better about not throwing it in the trash.