Corrosion of high-nickel stainless

P3-4 Corrosion of high-nickel stainless steel plates was found to occur in a distillation column used at DuPont to separate HCN and water. Sulfuric acid is always added at the top of the column to prevent polymerization of HCN. Water collects at the bottom cf the column and HCN at the top. The amount of corrosion on each tray is shown in Figure P3-4 as a function of plate location in the column. 

---