Copper strip corrosion

Carbonyl sulfide (COS), which occurs as an impurity in commercial sources of propane, can hydrolyze in the presence of water to form hydrogen sulfide (H2S) and carbon dioxide (CO2). All commercial and HD-5 grade propane is required to pass the copper strip corrosion test, ASTM Test Method D 1838. While it is known that hydrogen sulfide will cause the failure of the copper strip test, it is widely believed that the hydrolysis of carbonyl sulfide can also cause the failure of the corrosion test.