Ferric chloride, also called iron chloride, is a chemical compound with a chemical formula of FeCl3. It has a relatively low melting point, and its boiling temperature is around 315 degrees Celsius. When dissolved in water,ferric chloride undergoes hydrolysis and gives off heat in an exothermic reaction. It is produced industrially by the reaction of dry chlorine with scrap iron at 500 to 700 degrees Celsius.
In water and wastewater treatment operations, ferric chloride is used as coagulants or flocculants for odor control, phosphorus removal and hydrogen sulphide minimization. This is one of the few water treatment chemicals that can sequester odors. In the U.S., more than 80 percent of all ferric chloride is sold in municipal bids, with 65 percent sold for municipal waste water applications, and 18 percent for potable water treatment applications.