Carbon Dioxide → Magnesium bicarbonate

Reaction equation

[OH-:1].[Mg+2:2].[OH-].[C:4](=[O:6])=[O:5]>O>[C:4](=[O:1])([OH:6])[O-:5].[Mg+2:2].[C:4](=[O:1])([OH:6])[O-:5]

Participants

Procedure

Magnesium chloride solution (5.0 mol/L, MgO 200 g/L) is added into 30% sodium hydroxide solution by Na/Mg molar ratio of 1 for a 25 minutes reaction at 20° C., to get magnesium hydroxide slurry which is then filtered to get magnesium hydroxide cake. The magnesium hydroxide cake is mixed with water at liquid to solid ratio of 30:1 (calculated by the weight of water and magnesia), and then carbon dioxide gas is introduced into it to carbonize continuously at 25° C. Aqueous solution of magnesium bicarbonate (MgO: 30 g/L, Fe: 0.3 ppm, Al: 0.4 ppm) is obtained after filtration.