Nickel recycling problem 5

[cknterprise]

Hello everyone! We have a large quantity of paint masks made with nickel inserts soldered into steel frames. Each mask is on average 2' square with around 3 lbs. of nickel per mask. We're trying to recover as much nickel as possible as cleanly as possible to recycle and get a good value. The solder is 50:50 tin/lead.

We could heat the frames and remove the nickel inserts, but there would still be a substantial amount of solder contamination on the nickel. I've been told (although I haven't verified this) that contamination will bring down the value of the nickel substantially. Does anyone have any suggestions as to how to proceed with this? I'd appreciate any guidance.

 

[moltenmetal]

You've got to remove the steel first- that's a no brainer.

Heating the nickel-contaminated strips in concentrated acetic acid might dissolve the lead and leave the nickel, but I'm not sure what you'd do about the tin.

 

[IRstuff]

Have you tried the Nickel Institute?

http://www.nickelinstitute.org/1/1/index1.shtml

TTFN

FAQ731-376

 

[CoryPad]

Can you do mechanical removal of the solder? It will only be at the surface, so you can cut/grind/sand it away easily.

 

[EdStainless]

How about just cutting them out of the frames? you would leave the solder and a small amount of the Ni, but you would have most of it and it would be clean.

= = = = = = = = = = = = = = = = = = = =
Plymouth Tube

 

[cknterprise]

Thanks for the suggestions! I have tried the Nickel Institute, I emailed them and am waiting to hear back.

Like moltenmetal suggests, I definitely have to remove the steel. I've thought about both mechanical removal of solder and cutting them out of the frames. Both are definitely options. We have about 2000 of them, so I'm concerned about efficiency and time more than anything. With that many I don't know if an acetic acid bath is practical?

It looks like my best bet will be to heat the frames, remove the inserts, and then grind off any excess solder. In some cases it will probably be more effective to just cut out the nickel like EdStainless suggested.

Thanks again, everyone

 

[saberblue]

If they are all the same size and shape why not make a die and just cut them out with a single hammer blow or push with a bench press?

 

[gtaw]

You will have to meet the environmental requirements when dealing with the lead and you will have to do blood testing to monitor the levels of lead of the workers.

Best regards - Al

 

[unclesyd]

How many panels do you have?

What is the width of solder boundary?

How thick is the remaining solder?

 

[arunmrao]

There are very good contributions made. I do not know to which country you belong and the related pollution regulation norms. I would just recover mechanically,by punching or cutting,whatever Nickel I could economically get and would not be bothered with the rest( In fact disposing off,the rest also might prove to be head ache). Please remember,that attempting to remove lead by melting,would need special protection measures and the cost of these might obviate any economical advantage.Added to it is presence of tin.

In my career,I have always declined to undertake such risky missions,though on paper it appeared lucrative. The temptaions are strong,but the risks are also too many. Just my humble opinion on the subject.

 

[moltenmetal]

arunmrao, most people would just chuck these into the steel recycling bin without a 2nd thought. The lead would then become somebody else's problem.

Your cautions about the environmental and health and safety consequences of doing this wrong should certainly be paid proper attention. That said, considering how much environmental damage is done in the mining and refining of fresh mineral resources to replace the ones we waste, more people should be thinking like the OP - for environmental rather than purely economic reasons.

 

[blacksmith37]

The solder should wipe off (with a rag)pretty easily at 200C +/-.I would be suprised if any remaining trace would hurt the price. Pb :Sn will volatilize readily in a Ni alloy furnace.
History: 50:50 was the best solder to use for auto body/fender work before polyester/fiberglas in the 1960's. It was not a health problem in body shops.

 

[unclesyd]

All those body workers are like the old lead burners, they are dead and it wasn't because of old age.

As posted above shear off the part with the solder, sell as mixed metal. Sell the remaining nickel as good material.
I checked the two biggest scrap people here and neither one would give fair market value for the good Nickel. The reason stated is they don't handle enough of the material to make it worth their time. So you may have to look around for a buyer for your Nickel. I would check around to see what penalty you would take for contaminated Nickel.

Also as above you might wipe the solder off with a piece of ceramic textile fabric, I can't tell you what we used to wipe solder, but it starts with an "A"

If you have a large quantity of solder on each piece you might want to make a wooden paddle, soak it in oil to use to wipe the solder off.

Other possible ways to remove solder.
We used a molten salt bath operating about 150°F above the liquidus of the solder. I don't recall the salt mixture.

On small parts and low quantities we had a vacuum apparatus that worked like the ones used for CB's but larger.

Depending on the quantity needed to be removed, you might look at the cheaper pure copper scrubbing pads. Make sure you flux the copper.

 

[blacksmith37]

If you are in the US, you might give Specialloy in New Madrid MO a call. They formerly recycled high alloy (Ni) in Chicago. But now they concentrate on copper alloys, according to the internet.
The best of both worlds , they should be able to take your material to make "german silver", white colored brass alloys where a little lead and tin would not matter.

 

[dragracer9]

I used to manage a scrap yard and my advice is to desolder with acetaline torch. Then while still hot enough to keep the solder wet, drop them on concrete floor. Jusr be carefull of the solder splatter... You will not hurt the nickle.