Will Sodium Hydroxide Remove Copper

[uscra112]

No, I don't wan to create a new bore cleaner. The other day I was helping a friend rebuild the carbs on his antique Laverda SFC, (motorcycle). He had a bottle of nasty grease-cutter that he was using. It really did a number on my skin. I looked at the bottle later, and sodium hydroxide was the main ingredient. Now, I've been rebuilding motorcycles since 1966, but I never used this stuff, and since he seemed to know about it, I followed his lead. Thing is, we did not water-wash the parts down after cleaning the congealed gas out, just blew them dry. Now I'm wondering if those carbs' brass parts are slowly dissolving themselves, because just tonight I looked up the ph of the stuff, and it's about 14. In aqueous solution that is probably less, but ammonia is only 11. Any chemists out there ? ? ?

[MtGun44]

Burn you skin and corrode aluminum really quickly. Not user friendly at all. It will rinse
away with enough water, but will leave a corrosive residue if not adequately washed away.

Get it in your eyes and you could be blinded. If you touch it with bare skin, it feels slippery
because it is converting you skin oils into soap. . . . . Very nasty chemical.

Bill

[SASFixer]

Main ingredient in hot bluing salts. Won't hurt the bluing on a gun. I use a mild solution in an ultrasonic cleaner.

[Milsurp Junkie]

Former Chemist here (although mainly synthetic organic chemistry)
Sodium Hydroxide will not remove copper. Ammonia solutions work because the ammonia forms a copper-ammonium complex (chelates it). Sodium Hydroxide works to remove oils and tars by the same process that is used to make soap (saponification). Acetone, or mineral spirits would work by dissolving the tar/oil/grease by its solvent action.

[uscra112]

Former Chemist here (although mainly synthetic organic chemistry)
Sodium Hydroxide will not remove copper. Ammonia solutions work because the ammonia forms a copper-ammonium complex (chelates it). Sodium Hydroxide works to remove oils and tars by the same process that is used to make soap (saponification). Acetone, or mineral spirits would work by dissolving the tar/oil/grease by its solvent action.

That's the answer I was looking for. Thanks !

Saponification - is that part of what's in Gunk, then, I wonder?

Yeah the stuff was nasty alright, even at 20:1 dilution. Didn't burn, per se, but within half an hour my left hand, which was getting most of the contact, was all wrinkled like when you've been in the water too long. Friend's wife handed me some coconut oil, which helped a lot. We used that to lubricate all the rubber boots and whatnot as we re-assembled the bike. Edible, too! BTW no lasting effects from this contact, in case you were wondering.

Hey, Milsurp - maybe you know what's the story with this BC-10 cleaner product that's being touted by Gunzilla. It took me over an hour last night to track down the MSDS. They don't have it on their web site, as most companies would do as a courtesy. When I finally found a copy, it told me next to nothing. How can a biologically derived chemical remove powder residue, plus both copper and lead, as they claim, and still have the benign health hazard characteristics they state? Is it related to these citrus cleaners? Inquiring minds, and all that. In any event I doubt I'll buy any - at $129 a gallon it does not compare very favorably with Ed's Red.

[Milsurp Junkie]

Send me a PM with the information on it, and I will try to figure out what is going on with it.
A lot of plant based/derived material contain chelating agents that would dissolve or bind various metals. That could be what they are using, but I need to read a bit more about what they are using.

Milsurp Junkie.

[uscra112]

Send me a PM with the information on it, and I will try to figure out what is going on with it.
A lot of plant based/derived material contain chelating agents that would dissolve or bind various metals. That could be what they are using, but I need to read a bit more about what they are using.

Milsurp Junkie.

That's the problem, there isn't any information available. MSDS tells you very little, and nothing about actual contents, except that the formula is registered as a trade secret in New Jersey. But the fact that "a lot of plant based/derived material contain chelating agents that would dissolve or bind various metals" makes it all credible. I have heard the term "chelate" since high school, but have never learned how it works at the molecular level. Time for me to do some reading.

Phil

[Milsurp Junkie]

Chelating just means "binds". Most of the chelating agents EDTA (ethylene diamine tetra acetate) form rings around the metal, where the positive charge of the metal ion is surrounded by negative ions on the chelating agents. Depending on what is attached to those chelating agents determine whether or not it will be soluble in polar (water, alcohol) or non-polar solvents (mineral spirits, ether, etc). Then you can also influence the "hole" in the chelating agent with pH, allowing larger metal ions to not be bound, while binding smaller ones and vice versa.

PM me and we can discuss in more detail, or if people are interested, I can keep babbling

Milsurp Junkie.

[felix]

DO NOT USE PM'S. Spill all here so it can be captured by those having interest. ... felix

[runfiverun]

yes please.
i was gonna p.m. milsurp junkie about joining in on the lube thread some more also.

[uscra112]

Well, y'all, try reading the Wiki article on chelation. Took me under 5 minutes to get there. I'm still digesting.

[Milsurp Junkie]

Point me to the lube thread, and I can join in there as well.
Chelating agents and their uses are an entire industry. Maybe a couple of more than that as most of the enzymes in our bodies use some sort of chelating agent bound by proteins that use the metal ion to catalyze the reaction. For example, hemoglobin is a chelating protein that binds iron in the center of the molecule (allowing it to bind and release oxygen to our cells), and chlorophyll does essentially the same thing with magnesium to harness the photons from the sun to drive the creation of sugar from CO2.

Milsurp Junkie

PS- It is good to be able to explain chemistry to people, I have been out of the chemistry world and in the computer world for more than a decade...It is nice to use it besides reading the ingredient labels to see if I really want to put that stuff in my body.

[Bent Ramrod]

Strictly speaking, the cuprammine compound formed when copper dissolves in ammonium hydroxide is a complex rather than a chelate.

Get some Sweet's 7.62. It has enough ammonia in it to dissolve via complex formation any reasonable amount of copper fouling and some kind of thickener to make it adhere to the length of the barrel while it does it. You might need to alternate with regular bore solvents to get the layers of powder fouling that sometimes build up between the layers of copper fouling, but eventually you will see the time when the treatment no longer gets you a blue or green color out of the bore.

What sodium hydroxide will do is give you the quickest pair of dishpan hands ever. (This is a direct quote from my high school chemistry teacher, and, as usual, he was right.)

At 20:1 dilution, what the sodium hydroxide was doing was saponifying the oils out of your skin, making them cracked and painful. Rubbing emollients (oils) into your hands reversed the damage. If it was a 2:1 or a 1:1 dilution, it would have started to dissolve the protein in your skin, and a severe chemical burn would result. Not so easily treated.

[Milsurp Junkie]

Bent, you are correct that the copper ammonium salts are a technically a complex, and not a true chelating agent. Essentially though, the bonding mechanism and subsequent solvation of the metal ion is identical.

Milsurp Junkie

[shotman]

It will make a mess out of AL. I had some that was 10% and it cleanded very good . so Took a lawnmower piston that had lot of carbon bulid up. put in coffee can. 2 days later had the rings and wrist pin
your hands will look like an allagator