Is the corrosion of stainless steel by hydrochloric acid caused by acidity or by chloride ions?
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Is the corrosion of stainless steel by hydrochloric acid caused by acidity or by chloride ions? If hydrochloric acid is neutralized by sodium hydroxide, but the resulting salt, sodium chloride, still contains chloride ions, does corrosivity still exist? From the perspective of material selection for equipment, can stainless steel still not be used?
In a solution, at what level or above of chloride ions does corrosion of stainless steel need to be considered?
It’s not just chloride ions at 25 milligrams per liter; there are other acids and bases as well, which are listed on this 20581.
For hydrochloric acid, both are present; it mainly depends on concentration and temperature
It is mainly because chloride ions cause intergranular pitting in 304; using 316L would be better
Generally, the chloride resistance of 304 and 316 is several hundred ppm
25 ppm – it is primarily chloride ions that cause intergranular corrosion in austenitic stainless steel
If you need to remove chloride ions from water, contact me
The corrosion of stainless steel by hydrochloric acid is primarily due to a dual mechanism: first, the presence of chloride ions in acidic conditions has a significant corrosive effect on stainless steel. Under alkaline conditions, a good passivation film forms on the surface of stainless steel; however, in the presence of chloride ions, corrosion is generally minimal or does not occur at all.