Method for the selective acidic dezincification of steel scrap

Abstract

Complete dezincing of steel scrap is achieved by the addition of oils, whereupon the dissolution of iron is substantially suppressed through the autogenous inhibition effect of the oils. The steel scrap arising when the dezincing process has been completed is protected against corrosion by the remaining film of oil, the corrosion protection preventing the formation of iron oxide layers and thus blackening of the scrap material. The oil discharged with the dezincing solution can be separated as a pure phase by resorting to flotation in support of the process and can then be reused as an inhibitor.

Dependencies are inferred from the claim text.