What Is Calcium Oxide Used For?

By Staff WriterLast Updated Mar 25, 2020 8:45:44 AM ET

Calcium oxide, also called quicklime, is a chemical compound used in many different industries for different applications. In the metallurgy and steel industries, calcium oxide is useful for purifying or melting metals. Likewise, in the chemical industry, the applications of calcium oxide include as an absorbent and a dehydrating agent.


Calcium oxide has the chemical formula CaO and is a white crystalline substance. Because calcium oxide does not occur naturally, its production is generally from calcium carbonate or limestone. There are many commercial uses for this compound because it readily forms solutions with other substances like silicates. Some other uses of calcium oxide in other industries include the making of porcelain, the preparation of bleaching powder and the purification of sugar.

The iron and steel industries utilizes calcium oxide as a flux in the purification of scrap iron or steel. Calcium oxide can remove different impurities, such as phosphorus and silica from scrap materials. This process is important for refining and making steel products.

In agriculture and gardening, calcium oxide has applications as a fertilizer to treat acidic soil. Another commercial application of calcium oxide is in the construction industry that utilizes it in cement and mortar. Some other uses of calcium include as a water softener, in the making of glass and in the treatment of wastewater.