Electrolytic Etching

[Juless]

 

Hello In new here and I hope this is the right place to post

I found this forum while I was looking for some information about what was actually happening chemically when I did this project.

I am an art student and wanted to try etching designs into copper by the electrolysis method.

My set up was a DCell battery 1.5 volt. connected to a Copper object to etch on the positive end with and another piece of copper on the negative end. I placed them into a salt water solution of 180 grams salt to 500 mls water.

I would like to know what the brown and blue stuff is in the water I will attach a picture also I would like to know if any of the chemicals or gas emitted are toxic.

[EdEarl]

Is the salt, table salt, that is NaCl?

Did you use distilled water?

The red is probably copper oxide.

The blue might be copper hydroxide.

Black may be another copper oxide.

If your water has chlorine in it, you probably have some copper chloride (two kinds like copper oxide).

The bubbles are probably hydrogen, which is is very flammable...explosive.

The water may contain NaOH (lye) if you use chlorinated water.

 

There are some good chemists here that will point out any mistakes or omissions I've made.

Edited April 6, 2016 by EdEarl

[Juless]

Hi

Thank you for your reply EdEarl.

I used table salt and demineralised water. I had a feeling that there would be hydrogen and maybe oxygen coming out of the water.

I was really mostly concerned that it might be chlorine gas. Is there a possibility that the sodium chloride is breaking down to make that.

 

Also I was reading around this forum and found a topic about this where jdurg says in the thread

 

More copper electrolysis fun!

 

The electrolysis of an NaCl (Sodium Chloride) solution produces chlorine gas and sodium hydroxide. As the copper metal corrodes away, the copper ions will react with the free OH- ions forming Cu(OH)2 which will precipitate out of solution.

 

Is this information relevant to my project.

Edited April 8, 2016 by Juless

[foxy john]

If you are using a single D cell, I don't think you can generate enough of any thing to be seriously worried.

The hydrogen will disperse pretty rapidly in an ordinary room.

There is no chance that you could breath chlorine gas and not know anything about it

[Juless]

If you are using a single D cell, I don't think you can generate enough of any thing to be seriously worried.

The hydrogen will disperse pretty rapidly in an ordinary room.

There is no chance that you could breath chlorine gas and not know anything about it

 

 

So the bubbles coming off are defiantly hydrogen and chlorine but not enough to do any damage but still, I should work in a well ventilated area.

Thanks for your reply

[foxy john]

Not 100% sure about the chlorine being produced, it's most likely oxygen.

I'm afraid I'm a bit hazy now about electrolysis.

Try and work out a method for testing these.

[Juless]

Not 100% sure about the chlorine being produced, it's most likely oxygen.

I'm afraid I'm a bit hazy now about electrolysis.

Try and work out a method for testing these.

Lol foxy john I am an art student I have no clue as to how I would test for gas, I have only done very basic high school chemistry

Its more that the college encourages us use chemicals etc thought fully and be aware of the method of disposal of anything toxic.

We need to have MSDS info about any process we use.

This is not how they etch in the studio where I study, I'm doing this at home.

[EdEarl]

Bleach contains chlorine, so you might smell something similar if you are making chlorine gas. Don't stick your nose over the reactor to get a whiff. Best to have good ventilation and keep a few feet between you and the operating reactor.

[Juless]

Thanks EdEarl

I didn't notice any chlorine smell next time I use this apparatus I will defiantly keep my distance.

Do either of you guys who have responded know if this setup will work with silver. I have looked around the Internet and generally people use various types of acids.

[EdEarl]

I think silver and some other metals would work. You are essentially electroplating, a well developed science. Although, many industrial processes involve some pretty nasty stuff, such as cyanide and strong acids, and some plate metals like chromium, with wastes that are bad for the environment.