Magnesium oxide is used in agriculture to improve soil quality, promote plant growth and increase yields. The substance is used as a source of magnesium in animal nutrition and industrial animal husbandry.
Magnesium oxide is also used extensively in soil remediation and waste treatment. The ability of magnesium oxide to neutralize acids is used in drinking water treatment. School chalk consists of pressed, fine magnesium oxide powder.
Magnesium oxide is also used in rubber and caoutchouc production. It is also added to lubricants, adhesives and sealants to improve their viscosity (thin or thick liquid) and lubricity.
Magnesium oxide is often used as a filler or reinforcing agent in paints and varnishes to regulate their texture and viscosity. In wastewater treatment, magnesium oxide is used as a flocculant.
Magnesium oxide is also used to produce non-ferrous metals, steel refiners and glass. Due to its high melting point of 2,800 °C, the above-mentioned sintered magnesia is used to produce refractory and heat-storing materials as well as insulating coatings.
Magnesium oxide is used in organic chemistry as an adsorbent and vulcanization retarder. Air purifiers and filters are another area of application.