Junk_Enginerd
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Non polar/oil soluble copper salts synthesis?
I want to experiment with copper salts that are soluble in oil. The purpose is for outdoor wood preservation, sort of like pressure treated wood.
I know they exist, but I can't quite find the information I need to make it.
Through wild experimentation I've managed to find one way of making it react with candle wax. I can't say for sure if it's paraffin or stearic acid
candles. Copper oxide seems to react with said molten candle wax at ~200°C if oxygen is available. It dissolves and the solution becomes classic
copper blue. That's a step in the right direction, though I'd ideally light to dissolve it in a lighter oil if possible. It's not very "penetrating"
when it's candle wax. =)
The same reaction as described above doesn't seem to happen with liquid paraffin, mineral oil or mineral spirits. I tried it with linseed oil, but
it's hard to be sure what's going on there, since it gets a little trigger happy with its polymerization with the copper oxide and high heat, so it
just turns to black tar.
Any information on the subject would be interesting.
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Fery
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Maybe precipitating Cu soaps like CuSO4 (aq) + Na palmitate/stearate (aq) ?
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Pumukli
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Maybe using a,o-dicarboxylic acids (adipic-, suberic-, azelaic, sebacic acids) or trying to aim for the "middle range" in chain length of aliphatic
mono acids (C6-C10 range might be promising)...
Fery, when I tried, palmitic acid gave a pale blue waxy precipitate with CuSO4. It was very unpleasant to clean the Erlenmeyer after this stuff cooled
and attached itself onto the glass. I did this experiment eons ago in my childhood. (Finally I washed the Erlenmeyer last year. I told you it was
unpleasant...) 
[Edited on 16-8-2023 by Pumukli]
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Johanson
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"The purpose is for outdoor wood preservation"
The classic copper-based product was known as Cuprolignum. I just checked and it was apparently Copper naphthenate 34.5%
Chloroorthophenylphenol 2.5% and Petroleum Solvent 63%. I used it as a kid, and it was definitely effective. However, it is currently outlawed for a
whole host of reasons. I'm sure the same is true in Sweden.
In my experience, linseed oil and/or tung oil just sit on top, with relatively little penetration. They also dry to form a hard varnish-like top coat,
which would just lock in the copper on the surface. Thus, combining them with copper isn't really going to help you penetrate the wood cells.
Creosote works really well, as do solvent-based stains. Are you averse to these for some reason? If your wood needs to have a finished appearance,
like siding material for example, first staining with oil-based stain and then painting with acrylic or oil-based paint works well and looks nice. If
your wood is buried, like fence posts for example, creosote is your best bet. Copper is outlawed because it gets in the ground (and ground water) and
messes with the food chain.
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BromicAcid
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Johanson, that's actually what they still use, but less concentrated.
https://www.rustoleum.com/product-catalog/consumer-brands/wo...
That's what I use to paint the bottom of ground contact wood, looks like it's 3-10% Napthalate by the SDS.
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KoiosPhoebus
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Quote: Originally posted by Junk_Enginerd  | I want to experiment with copper salts that are soluble in oil. The purpose is for outdoor wood preservation, sort of like pressure treated wood.
I know they exist, but I can't quite find the information I need to make it.
Through wild experimentation I've managed to find one way of making it react with candle wax. I can't say for sure if it's paraffin or stearic acid
candles. Copper oxide seems to react with said molten candle wax at ~200°C if oxygen is available. It dissolves and the solution becomes classic
copper blue. That's a step in the right direction, though I'd ideally light to dissolve it in a lighter oil if possible. It's not very "penetrating"
when it's candle wax. =)
The same reaction as described above doesn't seem to happen with liquid paraffin, mineral oil or mineral spirits. I tried it with linseed oil, but
it's hard to be sure what's going on there, since it gets a little trigger happy with its polymerization with the copper oxide and high heat, so it
just turns to black tar.
Any information on the subject would be interesting. |
Maybe have a look into copper quinolinate (the 1:2 salt of copper and
8-hydroxyquinoline, also known as oxine copper). It's a broad-spectrum antimicrobial (https://www.jstor.org/stable/4547805) which is insoluble in water but should be soluble in organic solvents. 8-hydroxyquinoline is obtainable
where I am, and can be found in agricultural fungicides or as a lab reagent.
Here's an interesting resource from the USDA: https://www.fs.usda.gov/t-d/pubs/htmlpubs/htm06772809/page02... As other commenters have suggested, copper napthenate is also a good salt to look
into.
Another interesting option is to look into agricultural fungicides which form a complex with metals. A good example is prochloraz, an imidazole
fungicide which is typically sold as the manganese complex, but can also be found uncomplexed or as the copper complex. Unfortunately, this might be a
tad more difficult for you as the EU has (in my opinion, unduly) strict regulations on what fungicides are allowed.
I should also add that there are non-copper options like zinc or nickel which also possess antimicrobial activity (though you may have to use
different concentrations). A good example is copper + zinc being more effective than either in isolation (https://doi.org/10.1186%2Fs40104-017-0156-6).
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Junk_Enginerd
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Yeah... I'll give that a try. So you'd get Copper palmitate(or whatever) and NaSO4?
| Quote: Originally posted by Johanson | "The purpose is for outdoor wood preservation"
The classic copper-based product was known as Cuprolignum. I just checked and it was apparently Copper naphthenate 34.5%
Chloroorthophenylphenol 2.5% and Petroleum Solvent 63%. I used it as a kid, and it was definitely effective. However, it is currently outlawed for a
whole host of reasons. I'm sure the same is true in Sweden. |
None of the chemicals seems too bad at a glance. Certainly copper isn't something I'm too worried about. It's toxic, but that's sort of the point
yeah? =)
| Quote: Originally posted by Johanson |
In my experience, linseed oil and/or tung oil just sit on top, with relatively little penetration. They also dry to form a hard varnish-like top coat,
which would just lock in the copper on the surface. Thus, combining them with copper isn't really going to help you penetrate the wood cells.
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Yes. Ideally I would have liked to have the copper somehow dissolved in mineral spirits or some other light solvent to let it penetrate, and then
cover it with a polymerizing oil to seal the top layer and provide UV protection etc.
| Quote: Originally posted by Johanson |
Creosote works really well, as do solvent-based stains. Are you averse to these for some reason? If your wood needs to have a finished appearance,
like siding material for example, first staining with oil-based stain and then painting with acrylic or oil-based paint works well and looks nice. If
your wood is buried, like fence posts for example, creosote is your best bet. Copper is outlawed because it gets in the ground (and ground water) and
messes with the food chain. |
I'd prefer for it to look as natural as possible, but I honestly don't have big requirements. It's an experimental fun thing rather than anything
important. Just a tiny little bridge to cross a tiny little artificial stream. Mostly, I've found myself intrigued by the concept of "oil salts"
because it seems like such a weird thing. There are tons of products I can buy for the purpose, I'm sure, but it's more fun to DIY something when the
stakes are so low. =)
I mean, pressure treated wood is still chock full of copper, so it can't be too outlawed. Besides, surely a copper salt doesn't generally survive very
long once it is in the ground? I would expect it to be a little too reactive for that.
| Quote: Originally posted by KoiosPhoebus |
Maybe have a look into copper quinolinate (the 1:2 salt of copper and
8-hydroxyquinoline, also known as oxine copper). It's a broad-spectrum antimicrobial (https://www.jstor.org/stable/4547805) which is insoluble in water but should be soluble in organic solvents. 8-hydroxyquinoline is obtainable
where I am, and can be found in agricultural fungicides or as a lab reagent.[/font][/size] |
Wouldn't even know where to start looking for any of those or their precursors. =/
Yes, I found some info on that and it seems like the most straightforward thing to accomplish my goals. Googling either napthenates or napthenic acid
takes me nowhere unfortunately, it only provides academic papers which are far too advanced for me to grasp. It's sort of what I was hoping for by
trying to react copper/CuO with mineral spirits/naptha. Unfortunately it seems to be very non reactive. As far as I understand, naphtenic acids are
undesirable in petroleum products, and so they will be removed. Can they be made from purified naphta products somehow?
Interesting. I'll keep that in mind. Until I can dissolve either in a non polar solvent I can't do much though.
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Junk_Enginerd
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Now I tried it, it worked great! Took a bar of "artisanal" soap, figured it would be more likely to be simple sodium soap. I grated it into shavings
and set it to boil in a pot. Once dissolved, I added a copper sulfate solution. It turned cloudy immediately and I thought that was the precipitate I
was after. Whatever it was, it wasn't that, because it ran clean through a coffee filter like it wasn't even there.
After I boiled the mixture a bit longer I noticed the foam that was forming was carrying a deep blue oily substance that inevitably ended up stuck on
the sides of the pot. So I kept boiling it, and more kept forming. Once it seemed like it was done I could scrape a deep blue green, extremely goopy
goop off the walls of the pot. It behaves a lot like candle wax and seems to melt at a similar temperature, though it's stickier.
Most importantly, it effortlessly dissolved in both xylene and mineral spirits, while not dissolving in water. Fascinating. Mission accomplished! 
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Mr. Wizard
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pressure treatment of wood or other porous materials
Often wood is 'pressure treated' by submerging the wood in the liquid or solution and drawing a vacuum or low pressure on the container. Bubbles
coming from the wood indicate air spaces being evacuated. On release of the vacuum, liquid is pushed into the evacuated spaces. It does not always
require a large vessel as a plastic bag can be used to encase the wood or object while under vacuum and the liquid solution being admitted after the
vacuum. You can repeat by draining the bag and repeating the vacuum and looking for bubbles coming out. When it is completely saturated the bubbles
will cease.
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Fery
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Junk_Enginerd great! I expected similar as preparing Al palmitate/stearate used into napalm. I did the Al soap decades ago and also used my own soap
prepared from animal fats and NaOH. So thanks to boiling the precipitate of Cu soap changed into oil, that's good discovery! Because filtrating these
fine precipitates is impossible and drying even worse... good that you found a way how to separate it! This is the cheapest compound and from most
available reagents for every home chemist. CuSO4 and natural sodium soap.
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violet sin
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The soap and copper sulfate idea sounds like an easy and cheap win here. While reading I was reminded of something my father said years back. They
would buff copper handrails on the coast to a high shine, then paint them with diesel fuel... For when you wanted it bright copper color without
patina, in a salt water mist area.
Looking into this, you can find mention of copper mercaptan gels where distilled hydrocarbons and brass or copper alloys are in contact with
atmospheric oxygen. They clog needle valves, filters, orifices and the like on machinery.
Could be a different direction to look for sealing in copper metal on a wood surface. Say dust or shavings rubbed into the wood. Now it's not going to
penetrate in like a dissolved copper bearing substance, but the look or finish if you will, might be appealing for a rustic bridge. I think the
gelled stuff in diesel fuel was colored goop, the handrail was more like an oil paint accelerator for polymerization of the fuel to a varnish like
covering so only yellowed a bit.
Left me wondering what would happen with DMSO(dimethylsulfoxide), MSM(methylsulfonylmethane) might do? No idea if it would tell up or just stubbornly
coexist, as DMSO is pretty stable being used as a high temp solvent at times. Nor whether or not it would then dissolve in a solvent after
production.
I've always wanted to find some fun way to use para dichlorobenzene. From my limited reading there, it's stable and you almost have to lopside the
stabilizing halogens with Br or I to get it doing much. Again I'm not much more than an arm chair commentator at this point, so ... Use your own best
judgment and research. I just get to randomly research odd things here on SM for a few moments from time to time. The wells not too deep over this
way lol.
Good luck, thanks for some fun reading
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