CPC C01F 5/24 (2013.01) | 18 Claims |
1. An integrated process for carbon dioxide capture, sequestration and utilisation, which comprises:
a) providing an aqueous slurry comprising an aqueous solution and a particulate solid comprising an activated magnesium silicate mineral;
b) in a dissolution stage, contacting a CO2-containing gas stream with the aqueous slurry to dissolve magnesium from the activated magnesium silicate mineral to provide a magnesium ion enriched aqueous solution and a magnesium depleted solid residue;
c) recovering at least a portion of the magnesium depleted solid residue;
d) in a separate acid treatment stage, reacting the recovered portion of the magnesium depleted solid residue with a solution comprising a mineral acid or acid salt to further dissolve magnesium and other metals and to provide an acid-treated solid residue;
e) recovering silica from the acid-treated solid residue; and
f) in a separate precipitation stage, precipitating and recovering magnesium carbonate from the magnesium ion enriched aqueous solution.
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