Stainless Steel And Hydrochloric Acid Reaction

These oxides protect the steel from the corrosive effects of water.

Stainless steel and hydrochloric acid reaction. The common stainless steel types 304 and 316 should be considered non resistant to hydrochloric acid at any concentration and temperature. From the chemical results the corrosion rate of mild steel increased as well as increasing acid concentration with a reaction constant of 0 70 and 0 60 for he and wl respectively. Hydrochloric acid causes general corrosion pitting and stress corrosion cracking of austenitic stainless steel like 316. Stainless steel is stainless because there is a micrometer thin layer of oxides of chromium and nickel on the surface.

In hydrochloric acid stainless steels will pit and eventually fail. Corrosion resistance of stainless steel the iso corrosion diagram 0 1mm year lines are represented for 316 types red and a 6 molybdenum austenitic type green. Some types of storage tanks that have been used sucessfully include. If acid is spilled on your stainless steel sink or appliance it is important you rinse it off immediately.

The hydrochloric acid dissolves the oxides and begins to eat. The common stainless steel types 304 and 316 should be considered non resistant to hydrochloric acid at any concentration and temperature. In july 1996 the laboratory supervisor at a major stainless steel processing facility sustained a severe eye injury when a mixture of 25ml concentrated hydrochloric acid 25ml concentrated nitric acid and 50ml iso propyl alcohol burst through the top of the storage bottle and splashed into his right eye. When acid comes into contact with stainless steel a chemical reaction occurs.

Pitting and stress corrosion cracking can occur in dilute hydrochloric acid below the concentrations required for general attack. Higher grades of stainless steel can have limited resistance up to around 3 maximum at ambient temperatures but may suffer local attack mainly as crevice and pitting corrosion even at such low. The damage and possible corrosion if the acid is left on for long enough caused by this chemical reaction is irreversible.