Production of magnesium chloride and metallic magnesium from serpentinites of the Kutchinskoye deposit, Uzbekistan

Uzbekistan currently lacks domestic production of metallic magnesium and its compounds, which are widely used across various industries. Serpentinites from the Kutchinskoye and Arvatinskoye deposits are promising local sources of magnesium. This study examines the extraction of magnesium chloride and metallic magnesium through hydrochloric acid decomposition of Kutchinskoye deposit serpentinites, followed by silica separation and neutralization of the filtrate with ammonia to pH 8.5 for impurity removal and magnesium chloride solution recovery. Optimal conditions for magnesium chloride synthesis and dehydration were established, including artificial carnallite formation by adding potassium chloride. Acid treatment increased magnesium chloride content to 8.83 % and silica content to 78.53 %, indicating potential for silicate material applications. Electrolytic production of metallic magnesium was performed in an argon atmosphere, yielding 54.2 g of magnesium from 600 g of carnallite, with a recovery rate of 92.76–97.44 %. Additionally, ballast salts in the filtrate were minimized, achieving a magnesium chloride solution concentration of 71.38 %. These results demonstrate the feasibility of producing metallic magnesium from Kutchinskoye deposit serpentinites. Industrial implementation of this process can enhance raw material utilization, expand product ranges, and improve overall profitability.