K12Chemistry - 3-5-2013 at 10:16
I need to electrolyse copper sulfate to make sulfuric acid but i need an inert anode. Does anyone know any anodes that i can use apart from gold and
platinum? I heard someone used silver, would that work?
Pyro - 3-5-2013 at 10:18
carbon. nickel should work, SS too,...
Mixell - 3-5-2013 at 10:54
Don't use carbon, otherwise your sulfuric acid acid will be black.
Nickel will dissolve, SS too. Copper/silver might work (or they may corrode). MMO should not corrode. Best choice is platinum of-course, but it's
quite costly.
garage chemist - 3-5-2013 at 10:57
Acidic solutions of sulfates can be electrolyzed with lead anodes, which evolve oxygen. They get coated with a film of PbO2 which flakes off a slight
bit but if you filter the resulting solution before boiling down it's ok. The solution must not contain any anions besides sulfate.
Don't let the sulfuric acid concentration rise too much (above 50%) because lead is attacked by strong sulfuric acid.
Nickel is unsuitable, as is silver. Both are attacked.
Carbon can be used, whether it is a good choice depends on quality (EDM Graphite vs. gouging rods) and how strong the erosion is, which in turn
depends on current density and temperature.
Making sulfuric acid yourself this way is not viable. Buy it or forget it.
[Edited on 3-5-2013 by garage chemist]
K12Chemistry - 4-5-2013 at 03:05
OK so I am getting lead rods. Does anyone know where I can get some in the UK
garage chemist - 4-5-2013 at 03:27
Get roofing lead sheet instead. Should be available at the next metal goods store.
Hexavalent - 4-5-2013 at 14:01
Platinum-coated mesh or wire isn't horrendously expensive, and don't forget that it can be used many, many times again. I've almost always used carbon
electrodes for electrolysis, and simply filtered off the carbon particles when I'm done, using diatomaceous earth as necessary. Boiling the solution
for a while can also help to increase the size of these particles, making them significantly easier to filter normally.
K12Chemistry - 6-5-2013 at 05:58
Hey Joe do you know where I can get some platinum coated wire or mesh in the UK. Thanks