Cleaning Electrodes

trish armstrong · Post by **trish armstrong** » 27 Aug 2009, 10:59

Hi everyone,
My electrodes are pretty bad at the moment, anyway, was starting to do the hard task with the steel wool etc when a new teacher suggested I soak them in nitric acid and rinse really well.

Has anyone done this before does it work or is not worth the time?
It would be great not to have to do all that scrubbing.
And does it take off copper plating.
Will experiment on some old ones and compare to replys.

Trish.

lada · Post by **lada** » 27 Aug 2009, 11:16

Hi trish,
what type of electrodes are they? Nitric will take off Cu coating.
I still find steel wool the best. I do it after each use and then is not such a hard

task.
Lada

Voice · Post by **Voice** » 27 Aug 2009, 11:54

Nitric Acid with Copper will give you an unpleasant surprise if I remember correctly. I think it is nitrous oxide that is produced. Not nice..................
Maree

trish armstrong · Post by **trish armstrong** » 27 Aug 2009, 12:16

well I tried it though must admit didn't leave them in for more than 5min. Didn't do anything to the copper coating, the rusted ones cleaned up a little but not perfect.
Will have to torture the fingers with steel wool.

Thanks.
Any other ideas will be great to hear!
Trish.

smiley · Post by **smiley** » 27 Aug 2009, 12:18

I use conc Nitric in the fume cupboard. I have either a little beaker of it, or sometimes a dropper, and a BIG beaker of water to rinse. You can dip electrodes in the acid, then lift out and rinse, then repeat. The fume cupboard deals with the yukky Nitrous dioxide gas. It's actually really good for cleaning those little wire coils on calorimeters too. I use a dropper on them, and let the conc acid fizz off the copper. I keep dipping the coils in water,so that I don't dissolve the coil entirely. With patience you can have a nice shiny nichrome coil at the end, ready to go again.

bigmack · Post by **bigmack** » 07 Nov 2017, 10:45

Everyone has a draw full of Rusty old electrodes .
The teachers complain every time they use them .

Here's an easy way to clean them which doesn't require much elbow grease .

Sprinkle about 1/8 teaspoon of Sodium Carbonate (washing soda) into a beaker of water .

Connect the Negative to the electrode you want cleaned. Then place a piece of old iron or steal in the beaker and connect it to Positive . I actually use two pieces of iron and place the electrode between them so it does both sides at once

Set-up.jpg

Leave them in there for about 1/2 hour .
The beaker will look really scungy due to all the Rust that's being removed ......but that's OK
I usually do 3-4 before changing the solution

Gungy.jpg

When you remove the electrode it will look all black .Give it a scrub under the tap with a scourer and thoroughly dry .

Scrub.jpg

Before and after.jpg

It works well for other Electrodes as well but be careful when scrubbing the lead ones to wear gloves .

Zinc.jpg

Teachers are very happy and say experiments work as they should

J · Post by J » 08 Nov 2017, 09:20

Thanks, Richard.

bigmack · Post by **bigmack** » 08 Nov 2017, 14:30

Thanks J ....Haa you have to be the exception , IIRC your draw of electrodes are pretty good

J · Post by J » 09 Nov 2017, 07:50

Only because I had a clean out not long ago and bought some shiny new ones!
I have the old grungy, bent and dodgy ones stored away for various metal experiments. They come in handy sometimes.

trish armstrong · Post by **trish armstrong** » 09 Nov 2017, 11:58

Thankyou very much Bigmac for finally sharing. Gave this a try and worked fantastic.
Just greatful after 8 years I can stop sandpapering them.
Cheers Trish

Nat_ACT · Post by **Nat_ACT** » 28 Jan 2021, 11:47

I've got some Cu electrodes that were left in a beaker of water with Pb electrodes over the break. I've cleaned them up pretty well with carborundum paper but they could really do with more, especially around the bolts. I know I read on here about an easier way to do it but I can't find that again. The bolts really need it and carborundum paper isn't going to work. Thanks!

Post by **Labbie** » 28 Jan 2021, 11:58

There are some very good tips in this thread, Nat, good luck

Nat_ACT · Post by **Nat_ACT** » 29 Jan 2021, 14:04

Labbie wrote: 28 Jan 2021, 11:58 There are some very good tips in this thread, Nat, good luck

Thanks for that

Post by **Labbie** » 30 Jan 2021, 11:58

You are most wwelcome

bigmack · Post by **bigmack** » 31 Jul 2026, 12:08

Cleaning Carbon Rods

Thought I had put this here already .Today I had to clean the copper plating off a few Carbon rods .
Sanding it off is messy and wears the rods away .This way is less aggressive .

You need a beaker of 0.1mol/L Hydrochloric acid and a strip of old copper .
Connect up to power supply .
Negative (Black) to copper
Positive (Red) to Carbon rod
I use 12 volts but less is OK , just slower.

Cleaning Carbon electrodes 1.jpg

Here is the copper plating .

Cleaning Carbon electrodes 2.jpg

There is a lot of bubbling .It produces Chlorine gas .Not much , but if you are sensitive , do it in the Fume hood .

Cleaning Carbon electrodes 3.jpg

Just a few minutes later .....copper is gone .

Cleaning Carbon electrodes 4.jpg

EDIT: Doh ,I just found it
https://www.chemtalk.com.au/viewtopic.p ... 404#p46404

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