ANS:C - chrome magnesite

Chrome magnesite is a type of refractory material used in high-temperature applications where resistance to corrosion and wear is essential. It is composed primarily of magnesia (magnesium oxide, MgO) and chromite (chromium oxide, Cr2O3), along with various bonding agents and additives. Here's an explanation of chrome magnesite:

1. Magnesia (Magnesium Oxide, MgO): Magnesia is the main component of chrome magnesite. It provides high-temperature stability and resistance to basic slag environments. Magnesia has a high melting point and excellent refractory properties, making it suitable for use in applications where extreme temperatures are encountered.
2. Chromite (Chromium Oxide, Cr2O3): Chromite is added to the magnesia to improve the refractory's resistance to corrosion, especially in acidic or corrosive environments. Chromium oxide forms a protective layer on the refractory surface, which enhances its durability and prolongs its service life in aggressive conditions.
3. Bonding Agents and Additives: Various bonding agents and additives may be included in chrome magnesite formulations to enhance bonding between the refractory particles and improve its mechanical properties. These additives may include clay, silica, alumina, and other refractory materials.

Chrome magnesite is commonly used as a lining material in high-temperature industrial processes such as steelmaking, particularly in areas subjected to severe wear and corrosion, such as the hot zones of steelmaking vessels like converters, ladles, and tundishes. It provides excellent resistance to the alkaline and acidic conditions encountered during steelmaking operations, helping to extend the service life of refractory linings and reduce maintenance costs. Overall, chrome magnesite is valued for its high-temperature stability, resistance to corrosion and wear, and suitability for use in demanding industrial applications.