Descaling steel by pickling - using fluoric acid soln. contg. ferric ions and electrolytically producing nascent oxygen in soln. to reoxidise ferrous ions

摘要

Scale is removed from steel products, esp. stainless steel by using an acidic, aq. HF soln. containing Fe(34) ions as additive in the form of a complex fluoride cpd. During the pickling process a gaseous and/or fluid oxygen contg. medium is passed into the soln. and electrolysed to produce nascent oxygen. USE/ADVANTAGE - Pickling wire and other long products. The nascent oxygen causes the Fe(2+) produced during pickling to be more readily oxidised back to Fe(34).