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I used hydrochloric acid to remove calcium deposits from a pot, but left some of the acid on the kitchen sink metal plate overnight. It produced corrosion stains like on the photo, that can't be washed away. Is there a way to remove the stains or make them less visible?

enter image description here

tmlen
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    I am still wondering why you were using hydrochloric acid to clean in the first place. Is that a common thing? To use it for cleaning? –  Apr 14 '15 at 17:36
  • I found that it quickly dissolves calcium deposits that are left in a pot after boiling water. – tmlen Apr 14 '15 at 17:51
  • Hydrochloric acid will eat through metal. It is used to etch circuit boards. It does so very slowly which is why it did not damage the pot, but the plate with was exposed overnight was not so lucky. I imagine the stuff is not that eatable either so I would stop using it on dishes. –  Apr 14 '15 at 18:03
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    Best use citric acid to remove the residues. It's not as agressive. – Julian Apr 15 '15 at 08:56
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    Use white vinegar to remove calcium deposits on materials near food and food preparation areas. It works and is not toxic. Treat heavy deposits repeatedly. – Stan Jan 14 '17 at 03:55

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Since it's actually etched into the metal, you'll need to buff the sink to a consistent finish. One method, assuming it's a stainless steel surface, is to use a mild abrasive with oxalic acid, such as Barkeepers Friend and clean and abrade the entire sink with a sponge or cloth. This will require a lot of rubbing.

If that does not produce a consistent finish, abrasive grits can be used, starting with a moderately coarse (low number grit) and finishing with one that gives an even matte appearance.

Do not use steel wool, which inevitably leaves embedded fragments that rust.

DrMoishe Pippik
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  • Bon Ami is another abrasive very similar to Barkeepers Friend, and seems to be a bit more readily available, nice answer! – seadoggie01 Apr 13 '15 at 20:19
  • Bon Ami is a good general-purpose cleaner, but id does not have an acid etchant and passivator for the stainless steel. One could buy oxalic acid and add it to a non-chlorine abrasive cleanser. – DrMoishe Pippik Apr 13 '15 at 21:42
  • Oh, sorry! I was told they were the exact same thing, thank you! – seadoggie01 Apr 14 '15 at 20:59
  • @DrMoishePippik I don't know if the BKF marketing materials are actually true, but I remember reading them claim their combination of chemicals is more effective than straight oxalic acid, and also less hazardous. I'm not sure, but Barkeeper's Friend works like a dream but other acids I've tried for cleaning do not. – piojo May 23 '20 at 15:08
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I had the same problem - the stains on my stainless steel sink were caused by pool acid. I used Brasso and the stains are completely removed.

Nicolene Erasmus
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  • Please add some explanation to help OP out. As it stamds currently, it more looks like a comment. – A J Jan 15 '17 at 05:05
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I have just buffed out hydrochloric acid stains in my kitchen sink using a car cutting compound with the aid of a felt pad on my Dremil rotary tool. It has come up very well, hopefully my wife will only comment on how shiny the sink looks!

carl Hooper
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I used so much hydrochloric acid on a glass shower wall that the fumes discolored all the chrome fittings brown or green! Luckily It came off everything with cleanser and baking soda. Everything turned out well except the glass, which still has hard water marks after half a litre of 30% acid. :P :P

Tom King
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