What are the two main commercial methods for producing magnesium metal?

The commercial production of magnesium metal is achieved through two primary, distinct methods:

• Electrolysis: This process involves the dissociation of magnesium chloride into magnesium metal and chlorine gas within electrolytic cells. The feedstock is typically prepared from dehydrated magnesium chloride brines or through the chlorination of magnesium oxide.12
• Thermal reduction: This method utilizes the Pidgeon process (or similar variations like the Bolzano or Magnetherm processes) to reduce magnesium oxide. In this approach, calcined dolomite is typically reduced by silicon under vacuum conditions to produce magnesium vapor, which is then condensed into solid metal.13

While electrolysis was historically the dominant method, the Pidgeon process has become economically significant in the 21st century, particularly in China, due to lower labor and energy costs.14