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-----Rust from Muriatic Acid Fumes
We recently cleaned one of our machines using a mixture of hot water and muriatic acid
⇦ on
eBay or
Amazon [affil link] . We noticed that in our shop metals were rusting. How long will muriatic acid fumes continue to rust steel? Is there anything that can be done to neutralize this ?
Joe
Manufacturing, Electronics - Haveloc, Ontario, Canada
2007
2007
Hi Joe,
The muriatic (hydrochloric) acid vapor is long gone. Residual chloride (from the initial HCl-steel reaction) absorbs humidity and will continue corroding indefinitely. Possible fixes: wash with an alkaline detergent (TSP preferred) solution, then paint or wash with a water-soluble car wax
⇦ on
eBay
or
Amazon [affil link]
.
Caveat: If you ever want to paint or plate the material, avoid waxes containing silicones or fluorocarbons.
For future rust removal, use gelled phosphoric acid (e.g.,
naval jelly
⇦ on
eBay or
Amazon [affil link]
) per instructions. This leaves a somewhat protective phosphate film suitable for painting. tannic acid
⇦ on
eBay
or
Amazon [affil link] -based rust converter
⇦ on
eBay
or
Amazon [affil link]
s are weaker but require much less rinsing.
- Goleta, California
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