Process for the Extraction of Lithium from Dead Sea Solutions

Abstract Lithium is precipitated as lithium aluminate from Dead Sea brines, which contain a minute amount of lithium chloride, by adding aluminium salt and alkali (preferably ammonia) at room temperature. The process can be carried out in the presence of chlorides of magnesium, calcium, sodium and potassium. The lithium aluminate precipitate is dissolved in sulphuric acid and the excess acid neutralized with ammonia. The sulphates of ammonia and aluminium thus formed react to yield the respective alum. The solution contains lithium sulphate. The sulphate ions from the alum are precipitated with calcium chloride. The filtrate contains ammonium chloride and aluminium chloride. Aluminium chloride is precipitated by alkali to form aluminium hydroxide and recirculated as a soluble aluminium salt.