Lye and copper

[Cquence]

I did a first attempt at making lye using wood ashes (potash).
I used 2 copper kettles one with holes drilled in it, the other one to collect the potash. I put the ashes into an old cotton bedsheet that I tied so the ashes where contained as much as possible and I put it into the copper kettle with the holes. I've put a wooden bar trough the handles and put it onto some crates. Then I placed the other copper kettle underneath it and poored some rainwater over it.
Now I did leave it in quite some time, guess a month or so, because I didn't really had time to look after it anymore. Now I found that my kettle turned green and crystals had formed in the lye. The lye also looked a little greenish. I dissolved the crystals by adding more water to it and put everything in glass jars. There was a residue on the bottom of the jars, so I tried to decant it the best I could. It now already looks more yellow and less green. So my question is, is this lye still good to use? Can I still make soap out of it? Is it safe to use? Maybe I can't use it for washing hands, but still for cleaning, or is this still a risk, meaning I could damage the surface I'm trying to clean? What are other safe materials to use when making wood ash lye? I did the potato test, and it didn't float, so I guess I'll have to cook it, not worth the effort if I can't use the lye anyway, so that's why I'm asking here to get some advise. Hope somebody can help me with this.

 

[earlene]

Traditionally, lye hoppers were made of wood or your could use a steel barrel or stone.

Below is a photo of a v-shaped one that I have seen in various National and State Parks where displays about colonial days are in evidence.

Wooden Barrels were also used. But I have seen people use HDPE plastic buckets with holes drilled in the bottom and that is lye safe. I have also seen some people use large terra cotta planters as well. I believe the terra cotta planters would be safe to use, but would deteriorate, whereas the plastic bucket would remain useful for a very long time. Five gallon HDPE plastic buckets are easy to come by at a variety of places, especially in large home-improvement stores.

 

[Cquence]

I've read on the internet that copper would be safe to use and wouldn't react to lye, guess this information was incorrect. I've also read about stainless steel. Not sure if this will work.
Doesn't really matter right now.

Main question is, can I still use the lye I produced in my copper kettles for soap? Would this be safe to use?
I hate to throw away things...

 

[shunt2011]

I've read on the internet that copper would be safe to use and wouldn't react to lye, guess this information was incorrect. I've also read about stainless steel. Not sure if this will work.
Doesn't really matter right now.

Main question is, can I still use the lye I produced in my copper kettles for soap? Would this be safe to use?
I hate to throw away things...

I'm thinking it may be contaminated. Especially sitting for a length of time in the kettle. But not positive on it. Also, you will only get soap paste using ashes. It's KOH not NAOH.

 

[Cquence]

I don't consider having a soft soap as a problem, I often use soft soap already.
However the copper contamination does worry me...

 

[Kittish]

It may not have reacted with the lye, but copper will corrode if left in direct contact with air and water for extended periods. I'd think a month would do it. The green is probably oxidized copper.

 

[lenarenee]

Traditionally, lye hoppers were made of wood or your could use a steel barrel or stone.

Below is a photo of a v-shaped one that I have seen in various National and State Parks where displays about colonial days are in evidence.

And that hopper is the birthplace of my fascination with soap; you'll see under the picture it's noted as being from Lincoln's New Salem - a place I visited a dozen times as a kid. I never tired of hearing about how the ashes were rained on and the "goo" was cook with fats to make soap.

Btw, they would actually make soap there on occasion. It was nasty stuff.

 

[Cquence]

@Kittish
Yes, that would make sense, and the reason it is getting more yellow as impurities sink to the bottom. I might do some research if it would be possible to filter the lye! Thanks for the info!