It is used extensively in industrial cleaning operations. Test data is shown on sulfuric, sulfamic, phosphoric, formic hydroxyl acetic, formic, and acetic mud acid and citric acids. CRONOX™ CRO240 corrosion inhibitor is an effective inhibitor on mild and high carbon steels at temperatures ranging up to 200°F (93°). Optimum inhibitor concentrations for acidizing systems containing cast iron or special alloys should be determined experimentally.