In the manufacture of alkyl amines, ammonia is reacted with an alcohol to form amines. The reaction is carried out in excess ammonia that is subsequently removed by distillation. One of the by-products of the reaction is carbon dioxide which reacts with ammonia to form carbamic acid. This acid concentrates in the column and becomes corrosive to type 316 stainless steel. For some of the processes, the column and most of the trays are fabricated from alloy 2205 to resist corrosion from carbamic acid.

Organic acids tend to concentrate in other areas of the process as well. These accumulate in a reboiler and become corrosive to type 316 and also to alloy 2205. The material of choice is alloy 2507 which has given reliable service for the heat exchanger.

Acetic acid is produced as a by-product in the polyvinyl alcohol process. The standard material of construction is type 317L for the distillation towers. Residual chlorides accumulate in one column and become corrosive to stainless steel. Alloy 2205 is used for tray material in certain portions of the column and for the chloride removal system. This alloy offers increased corrosion performance over type 317L and is less costly than titanium.