Anyone know anything about electroplating?

[ThegunGuy]

I have been experimenting with copper electroplating and I am getting poor results. Anything that I put on the negative electrode gets covered with a dark red sludge and gets a tiny amount of actual plating on it. Anyone know what I am doing wrong, I think i am using a 5% sulfuric acid solution and only 1.5 volts it gets the job done but I use three ounces of copper to get a tiny layer of plating. Has anyone done this before I checked all over the internet and found nothing, so thanks for any help.


By the way we are having the longest and coldest cold streak here in Oklahoma had this going outside and it started to ice over. Global warming?

[Gippeto]

It's been a long time since I last darkened a door to a chem class. I seem to remember using a solution of distilled water and Cu2SO4...but like I say...it's been a long time.

Tried google?

http://www.google.ca/search?hl=en&q=cop ... =&aq=f&oq=


Yeah, global warming my frost bitten arse...the expected high for Sunday here is -30C.

I friggin hate winter.

[ThegunGuy]

I thought I might need copper sulfate to do it. The solution appears to be turning blue green as the red sludge disappears, which might explain why its taking so long. Do you think I should put some of this unknown sludge into some 40% sulfuric acid? I know its only copper and some other part of the sulfuric acid forming the sludge and I know its the copper sulfate turning the solution blue green. Lol glad I just reasoned out not to put it onto a hotplate to speed it up. hotplate+H2= police knocking at the door again. just kidding we know them well enough now. Sad to be on a first name basis with the authorities and the nurses in the ER (not me its my family doing it. My brother taught us all that you only need 15 mph to destroy a really expensive recumbent bike).


At least "Global Warming" is giving me a chance to test out my cold weather gear I have more hi performance cold gear than warm gear, and here 40 fahrenheit is about the coldest it gets normally in the winter. Last year I went swimming in December on purpose without getting hypothermia. even though it wasn't a very long swim.

[Biopyro]

Gippeto is right, you'll need a solution with copper ions in it and two te anode must be copper.
That way, copper ions are removed from the anode and go into the solution and at the cathode, copper ions are immediately deposited again. A sufficiently saturated solution of copper ions should prevent your problems, but make sure that both metals start off clean.

[rp181]

you are going to keep getting very poor results. Its nearly impossible to get a reliable plating without cyanide based solutions.

[john bunsenburner]

Here goes chemistry class:

To electroplate you need metal ions in solution that are positively charged (copper has a +2 charge, nickel does too, but there are exceptions) cations (as they are attracted to the cathode). Now to electroplate these ions have electrons forced onto them, two electrons in this case, the ions will then have no charge and change into solid metal which will, if done correctly, attach to your anode, the part to be plated. Now any ionic copper compound would, technically, do the job. For teaching purposes I will use copper sulphate, which in solution has a blue colour it is also fairly soluble and so good for these purposes.

You first make a solution which should be saturated with CuSO₄ (Copper Sulphate), at standard room temperature that is 31.6g. I could now work out how much of those 31.6g are copper, but that is of little use to you, what you should, however, know is that slowly the copper will be used up. To prevent that you use a copper anode, this will “pull” away two electrons from the copper thus release more copper into solution, like this you will never run out, technically if the anode is replaced before being used up. Your set up should look like in the attachment.

In practice you are faced with the problem that copper will not bond well to the piece, this can be improved by using cyanide based solvents(instead of water) but doing that at home, without a commercial set(which can get expensive) is asking for trouble. You can buy kits to do this, but if you only want to do this once or twice have your piece commercially plated, there are companies that do this and it will be cheaper than buying a kit and then only using it once.

[ThegunGuy]

I woke up today and in the low concentration acid the piece of brass I put in it was coated with copper just like it should be. The higher concentration solution however has turned blue and there is not much more copper on the metal. But it works. Isn't copper sulfate a salt? That would work wouldn't it? I think my sulfuric acid is stripping copper from the anode but is letting it dissolve in the solution instead of plating onto the metal. Why would I need two anodes? Might work better, but how would I do that?


edit: Sorry wrote this an hour ago but the internet went out before I posted it old info. And I also thought sulphate was spelled sulphate but spellchecker kept correcting me.

[ramses]

I'm no expert, but since you are adding an ionic copper salt to the water, you could most likely do without the H2SO4.

[Heimo]

Here are a few pages scanned from an electroplating book I got I will attach them these cover the electrolyte and some of the problems that you might encounter also try a bit higher voltage something between 4V-12V

[ThegunGuy]

Thank you so much for the help

Just went to the hardware store got a 6 volt battery forgot to get copper sulphide.

Another thing I just looked at my bottle of sulfuric acid and it is actually hydrochloric acid. I'm surprised I didn't blow anything up getting my chemicals confused like that. But I managed to electroplate something using hydrochloric acid.

[Heimo]

Thank you so much for the help



Another thing I just looked at my bottle of sulfuric acid and it is actually hydrochloric acid. I'm surprised I didn't blow anything up getting my chemicals confused like that.

I am really surprised you did not notice, hydrogen chloride (HCl) have a very distinctive smell

I don't think anything you had in that cell could have formed an explosive mix
the worst that could have happened is that you could have generated a little chlorine gas but I am just speculating here without really thinking about it

[jrrdw]

Global warming?

Elneeno winter!

[ThegunGuy]

Got the real sulfuric acid and am dissolving the copper into it now.
I had lead in a hydrochloric acid solution it was producing a lot of hydrogen and I was about to put it onto a hotplate, and it was producing a lot of hydrogen gas and lead chloride, dangerous stuff.

But I really am amazed that I could electroplate with hydrochloric acid.

[Heimo]

Got the real sulfuric acid and am dissolving the copper into it now.
I had lead in a hydrochloric acid solution it was producing a lot of hydrogen and I was about to put it onto a hotplate, and it was producing a lot of hydrogen gas and lead chloride, dangerous stuff.
Secrety!
But I really am amazed that I could electroplate with hydrochloric acid.

Ahmm why are you dissolving copper into sulfuric acid that is not necessary just follow the recipe on page one I posted ...or are you having trouble finding copper sulfide ? cause that is essentially what you are making by dissolving the metal in the acid?

[ThegunGuy]

I don't have any copper sulphate so I'm making it.