A possible way to remove zinc from molten lead

[Djei5]

Pouring melted lead on water? It doesn't explode?

Pouring water into melted lead does.

[AllanD]

OK Hold it right here. The muriatic acid in the above web site was suggested as a way of checking a mix of wheel weights to see if any zinc ones are present. Yes zinc would react as opposed to lead BUT all of the iron clips in the mix would also react. Adding Muriatic acid was NOT suggested as a way of removing zinc from a lead alloy containing zinc. It was a stupid suggestion coming from a physics teacher with obviously no clue of what is in a bucket of wheel weights.

Muriatic acid is a solution of hyrochloric acid (HCl). In its anhyrous form HCl is a gas at room temperature. You be the judge if the water or HCl will stick around until the lead melts.

Muriatic (Hydrochloric) acid will have only a small effect on lead at normal temps (attempting to clean lead flashing with HCl is a long slow process that would test the patience of any saint you care to name), it's main effect on steel and Iron is to rapidly remove any Oxides present, Ferous (III) Chloride is a bright yellow in aqueous solution, and is rather different than the fizzy, fuming fire monster (From liberated Hydrogen) that HCl reacting with zinc is...

Straight HCL is one of the best acids to clean your empty (Cold) melting pot...

[AllanD]

Not sure if road flares have any sulfur at all but they do have a lot of Strontium nitrate and wood meal. The wood meal provides a fuel and the Strontium nitrate is an oxidizer and colorant. It makes the flame red. I do believe there is pvc included too as it makes the color brighter and more red.



Frank

Frank,

Nobody intentionally burns PVC (at least not where the EPA will ever hear about it)
because burning PVC produces PCB's and Dioxin and several other such nasties...

Allan

[Traffer]

I recently used sulfur to remove possible zinc contamination. The sulfur seems to have ruined the batch of lead. It kept "taking more" so I kept adding more. When I had removed almost half of my batch in black and dark grey slag, I began to think, "maybe I am just making lead sulfate here". I tried melt down some of the slag and got a small amount of lead that has very large crystallization. What is left of the batch is now harder than when I started. I don't know if it will flow well, I can't use it because I need soft lead. Also, my recent ingots have a sour smell. I know that lead does not have a smell but these definitely smell sour. I am perplexed about all of this.

[Don Fischer]

Is this zinc coming from wheel weight's he smeltered? If so, its easy so separate to separate zinc from lead. Melt the wheel weight's at just over the melting point of lead. I think I melted at 600*. Anything that float's get's dumped.

[Traffer]

Is this zinc coming from wheel weight's he smeltered? If so, its easy so separate to separate zinc from lead. Melt the wheel weight's at just over the melting point of lead. I think I melted at 600*. Anything that float's get's dumped.

I am more interested in how to get rid of the sulfur at this point.

[triggerhappy243]

[QUOTE=AllanD;3578319]Frank,

Nobody intentionally burns PVC (at least not where the EPA will ever hear about it)
because burning PVC produces PCB's and Dioxin and several other such nasties...

Now here is an evil thought............... we want our lead back. so lets make a deal with the epa. Give us our lead back or we will start burning PVC. (SORRY, I DONT KNOW WHERE THAT CAME FROM). But who knows.

[triggerhappy243]

I am more interested in how to get rid of the sulfur at this point.

I have not tried using sulfur, yet, is it possible to use too much?

[Traffer]

I recently used sulfur to remove possible zinc contamination. The sulfur seems to have ruined the batch of lead. It kept "taking more" so I kept adding more. When I had removed almost half of my batch in black and dark grey slag, I began to think, "maybe I am just making lead sulfate here". I tried melt down some of the slag and got a small amount of lead that has very large crystallization. What is left of the batch is now harder than when I started. I don't know if it will flow well, I can't use it because I need soft lead. Also, my recent ingots have a sour smell. I know that lead does not have a smell but these definitely smell sour. I am perplexed about all of this.

I tried resmelting some of the wheel weight possibly contaminated lead that I previously tried using sulfur on. I am going to try and describe just exactly what I did so maybe someone can help me out here. I bought about 8 lbs of WW on eBay. The guy said that there were no zinc ones in it. I melted it down (I do not have a thermometer) and got a batch of pretty hard lead. I tried using it and it worked OK but not great. I am sure it was way hot enough to melt zinc. I used it again a couple of times and it seemed not to flow to well. Then I read the thread about sulfur. I don't mind experimenting so I bought some clay-sulfur at the garden store. I separated the sulfur out by literally picking out the little yellow balls from the brown stuff. I got about 6 oz of what I think is sulfur. I melted a small pot full of lead (about 4 to 5 lbs) and added about 2 tbsp of the sulfur. I put it on top and then pushed it under with a spoon with holes in it. I had the spoons tied to 4 ft sticks and I was wearing a respirator and was up wind while doing this. The sulfur burned, it bubbled in the lead creating big lead bubbles, then the lead that was in contact with the sulfur turned to a bubble gum like consistency, then it got harder. I kept mixing it until it turned to grey-black powder. A LOT of grey-black powder. I kept adding sulfur expecting it to stop "taking" it. It didn't stop taking it. I ended up using about a half a cup of sulfur in that 4 to 5 lb batch of lead. I piled the dross in another container to re-smelt at a later time. YOU CANNOT BE TOO CAREFUL WITH THE FUMES. I got just a whiff through my respirator and that even made me sick. Any way I made a few small ingots of the stuff and tested it for hardness. Hardness was the same, about 11BHN. The ingots seemed to cool with large crystals in places, kinda like cast iron. I can't use 11BHN. So my experimenting with it stopped. I did go back however and try to glean some more lead from the slag pile. I put in about 3 or 4 cups of slag and eventually got a small chunk of lead, about 4 oz. Oddly that lead had a kind of gold sheen on the surface and it ended up being 8 BHN. So because of that "luck" I took about 4 lbs of the previous sulfur-smelted lead and tried sulfur smelting it again. It went the same as the first time. Lots of sulfur, big bubbles, bubble gum consistency then black powder slag. But the lead poured beautifully and the ingots are very fine, no bubbles or large grain structure. It is 11 BHN though. So, I give up. This 11 BHN lead looks really nice but it is too hard for me. So I thought I would trade it to someone for some softer lead. Any ideas or comments?

[triggerhappy243]

Traffer, did you have the lead xrféd before you put the sulfur to it?

[Traffer]

Traffer, did you have the lead xrféd before you put the sulfur to it?

What is xrfed?

[badbob454]

scanned with a machine, to check alloy content.

[triggerhappy243]

most competent metal recyclers have them.

[Traffer]

I doubt if there are any around here. Besides I am dealing with a total of about 7 lbs of lead.

[triggerhappy243]

there are several members here that have access to the xrf gun. you could send a sample to them and they will have it tested. far better plan then to waste all that time trying to cook off the zinc that might not exist.

[Nose Dive]

Hmmm at February string ... about sulfur... Well... .it is NOT A CURE ALL FOR a good BRN... and not for pourability of the alloy...

I USE SULFUR in my SMELT pot and not in my casting pot. I do not alloy mix in my casting pot either....

So...here is my methodology...

I mix sulfur from the nursery in with my sawdust from my table saw. Put in bottom of smelt pot...and smelt...bring up temp and mix....

Say... three hand fulls of sawdust and one of elemental sulfur...mix it up in a cold smelt pot...cover to top of pot with smelt material...heat up...

SMOKE...smell...noxious fumes... mix things up.... have a 'filter' dipper and screen clips...zinc...trash...corruption.... stay UNDER 700F....stir..mix...

Ok...all smelt is melted...stirred up nice....now add more sawdust/sulfur and mix again.... mix....screen...clean.....

NOW...at 700F...bring up heat to 800 or so...and you guessed it...ONE MORE TIME!! but this time only sawdust and mix and screen well.....

Mix...strain...scarpe bottom of pot... at 800...after all dross is gone...I add a heeping hand full of wax and mix well again... look out..flames!!

So now...you are cool with zinc...you strained and fluxed it at 700...so ...why add more flux...you have done it four times...

Here... I alloy...add tin...I like PEWTER better.... mix it well... and stay around 800....NOT TOO HOT... Time to pour out into biscuit tins....

Yup... pour it out and let it cool...then BRN test... If to hard or too soft... ALLOY IN CLEAN SMELT POT...not casting pot...get it right first...

SO now you have casting ingots and get after that....

no need to go crazy with the sulfur if you flux with it at smetling time!!

Nose Dive

Cheap, Fast, Good. Kindly pick two.

PS; Guys...go back to page four...read all the discussion there too. ND

[AJG]

why would you get the Zinc out?
I have about 1/4 of all my wheel weights Zinc WW and the rest is lead (what melts).
I get wrinkled bullets and 3 of 6 cavities are filling correctly but who cares.
I can live with wrinkled bullets.

More of it seems Zinc is better for the Barrel than even lead. It is harder than lead but softer than copper. If left unsized it should fit perfectly and I Experiment no leading.
I use Lithium grease as bullet lube.
Just leave the Zinc in the lead and learn to cast it. It makes for usable bullets.

[spqr]

i stumbled into your thread while looking for zinc solutions. really helpful info, so i registered.
last weekend i polluted a 50lb smelting pot of nice range lead with some boneyard "lead". My buddy that owns the place gave me about 100# of scrap non ferrous they had been collecting since the 70's. Most of it was wheel weights i have since used. I came across big 3 ingots that looked a lot like Lyman casts, just a little different look. And a round diski assumed was plumbers lead. Looked like lead, and heavy. I assumed they were all lead. Mistake. I added them to the 50# i had molten, with about 6 oz of tin. Noted the constant oatmeal pooling at the top. I avoided it best I could, made about 2000 swc 45s and the rest into cupcake ingots for later. When I cast the 45s the mix flowed decent enough, I just had to keep ladling from below the oatmeal surface. They looked fine until they cooled. Then some of the bullets wrinkled. After the ingot "cakes" cooled I dumped the pan and noticed the hexagonal sparkle on the bottoms. They also bounced of the floor. Not the solid thump i expected. All ruined, probably way too high % zinc. I have been going through the bullets, about 10% are visibly wrinkled and were discarded. I sized the clean ones and they are going through my Lee .452 sizer in typical fashion. I sampled the usable ones and did a vice "hardness" squeeze against some old stock from a previous batch. Exact same hardness, or should i correctly say "softness". i have found "soft" does not lead the barrels at all. I guess the moral is, keep the temp down and avoid the zinc at the surface. Or avoid the zinc altogether. And yes, I cast right from the smelt pot. I am not a purist. I have a full time job and barely enough time to cast. I have pushed out around 10,000 very clean bullets in this manner in the last year and half, 3 of us fire these weekly and have had excellent groupings and no leading (2 1911s and a SW M&P) with 5.7 Unique and Alox ring 200 gr. bullets. No more mystery metals into the mix though. No disagreement with the previous post, I could load the hard wrinkled zinc/lead bullets, but I shoot at an indoor range and have seen chunks travel 30 feet back. I would be worried the zinc-based bullets would bounce too much.

[triggerhappy243]

spqr, for the cost of 1 pound of clean lead, and a penny sized splatter of your problem lead, you can have bne do an xrf test on your mistery lead. you can also put a few drops on the suspect metal of muriatic acid (aka pool cleaning acid). if it foams, it has zinc.

[Oklahoma Rebel]

AJG, not to be rude, but it sounds like you don't know what you are talking about, and you might give some newcomer the wrong advice. anything more then a few percent zinc is really going to mess with your casting, and boolit weight, and your lube may work for 800fps 38spls. but if someone listened to you and used it in their rifles they are in for a lot of cleaning. lithi-grease does make a good INGREDIENT for boolit lube. pls learn some more before giving out tidbits of wisdom!