摘要 |
A process for reducing the carbon dioxide concentration of a carbon dioxide-containing gas which process includes, in a first stage, contacting the carbon dioxide-containing gas with a treating solution including an alkali metal carbonate and/or hydroxide and with a catalyst to promote the absorption of carbon dioxide to form a second solution including an alkali metal carbonate and bicarbonate and, in a second stage, contacting the second solution with a carbonatable silicate-containing material including an alkaline earth cation capable of forming an insoluble carbonate to produce silica and a solid carbonate including the cation and to regenerate a solution including alkali metal carbonate. |