Patent ID: 6921523

Claim:
A process for preparing a magnesium thiosulfate solution comprising: combining magnesium oxide and water to provide a magnesium hydroxide slurry or hydrated magnesium hydroxide; adding sulfur dioxide to the magnesium hydroxide to form a mixture, and reacting the mixture to form a magnesium hydrosulfite slurry; adding sulfur to the mixture, and reacting the mixture under conditions sufficient to form magnesium thiosulfate; and recovering the magnesium thiosulfate solution wherein the process proceeds according to the following reaction pathway: MgO+2SO 2 +H 2 O→Mg(HSO 3 ) 2 Mg(HSO 3 ) 2 +2S+MgO→2MgS 2 O 3 +H 2 O.