Manganese chloride is an inorganic compound with the chemical formula MnCl₂. It is usually found in the form of dihydrate (MnCl₂·2H₂O), which is a crystal with water molecules that is highly deliquescent. Anhydrous manganese chloride is a pink solid, while manganese dihydrate is a dark green crystal.

Here are some of the main uses of manganese chloride:

1. Metallurgical industry: Manganese chloride is used in the production of manganese metals and manganese alloys, such as silicon-manganese alloys and manganese-iron alloys, which are used to make steel and other alloys.

2. Trace element fertilizer: Manganese chloride is an important trace element fertilizer that provides manganese needed for plant growth and helps to promote the normal growth and development of crops.

3. Chemical synthesis: Manganese chloride is used as a catalyst or reagent in organic chemistry to promote chemical reactions such as oxidation, reduction, and coupling reactions.

4. Drinking water treatment: Manganese chloride is used in combination with chlorine to act as an oxidant in drinking water treatment, helping to remove contaminants such as iron and manganese from the water.

5. Pharmaceutical: In the production process of some drugs, manganese chloride has been used as a catalyst or reaction intermediate.

6. Battery manufacturing: Manganese chloride is an important component of certain types of batteries, such as lithium-ion batteries and nickel metal hydride batteries, which are used to improve the energy density and performance of batteries.

7. Ceramics and glass industry: Manganese chloride is used as an additive in the ceramics and glass industry to help improve the color, strength, and heat resistance of products.

8. Animal feed additives: Manganese chloride is a trace element additive in animal feed that is used to meet the nutritional needs of animals for manganese.