underground
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Titanium etching
I would like to etch a titanium sheet with electrochemistry. Since i do not have access to HCL i was thinking to use an oxalic acid solution to etch
the titanium sheet at room temperature. My intention is make a Mno2 anode for chlorate production. Any thoughts ?
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Simoski
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clean, dry and wipe with acetone.
electrolyse in sodium hydroxide 50 grams per liter.
titanium as the anode.
20 minutes. 2amps 5 volts.
thats a guess
[Edited on 16-2-2019 by Simoski]
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underground
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Wow thanks
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markx
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Hot phosphoric acid (approx. 50%) will etch Ti very nicely. Ive used the method as a precleaning treatment for Ti before deposition of Pt.
The electorlytic etching approach will likely not work....passivation of the surface shall hinder any reactions. One can sort of etch Ti under anodic
potential, but the applied voltages have to be high and the resultant surface is not in a condition that can be called clean by any means.
Exact science is a figment of imagination.......
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underground
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Quote: Originally posted by markx  | Hot phosphoric acid (approx. 50%) will etch Ti very nicely. Ive used the method as a precleaning treatment for Ti before deposition of Pt.
The electorlytic etching approach will likely not work....passivation of the surface shall hinder any reactions. One can sort of etch Ti under anodic
potential, but the applied voltages have to be high and the resultant surface is not in a condition that can be called clean by any means.
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Any other way to etch Ti nicely? I do not have access to phosphoric acid too
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markx
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Well, you do not have to etch it as a "nonegotiable must". Just sand it clean with 240-400 grit wet dry paper and call it good. I really saw no
difference in the longevity of sanded Ti vs. etched one as anode substrate. Both were outstandingly mediocre. Don't sand it with a very fine paper
(above 400grit), the surface will become very hydrophobic and one can not wet it evenly with the Mn nitrate solution.
Also do not let the sanded Ti sit around, proceed immediately with the coating treatment after sanding. If left exposed to air the bare Ti will
quickly form an oxide coat that serves as a barrier which shall proceed towards passivation under anodic conditions.
Exact science is a figment of imagination.......
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underground
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Thanks a lot markx, really appreciate
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