Patent ID: 6355605
Filing Date: 2002-03-12
Classification: C11D

Abstract:
An aqueous cleaning composition for treating surfaces to remove iron stain and scale which consists essentially of:an acid selected from the group consisting of (a) hydrochloric acid in an amount from about 5 to about 25 wt. % and (b) sulfuric acid in an amount from about 5 to about 10 wt. %, an oxidizable stannous salt in an amount from about 0.5 to about 5 wt. % for reducing ferric ions to ferrous ions, a fluoride compound selected from the groupconsisting of potassium fluoride, ammonium bifluoride, and hydrofluoric acid in an amount from about 0.5 to about 5 wt. % for solubilizing scale, and water to 100 wt. %.