Feasibility of CO2 Fixation via Artificial Rock Weathering

Artificial rock weathering can potentially fix a large amount of CO2 generated from industrial and other sources with a slight expense of mechanical energy. From technological, economic, and environmental perspectives, artificial rock weathering is a preferential method to dispose carbon dioxide. Carbonate and hydrogen carbonate ions are formed spontaneously when carbon dioxide is dissolved in an aqueous solution owing to the negative Gibbs free energy. The calcium silicate component of wollastonite reacts with carbonate ions and becomes calcium carbonate and silicate. Such a reaction is economically feasible because this transformation does not require energy infusion. The products are naturally stable and can be discharged safely without pollution. Experimental results indicated that, in an aqueous solution, 1 ton of wollastonite could fix nearly 140 kg of carbon dioxide. No carbonation was observed when using talc under our experimental conditions. The study indicate that the reaction rate of artificia...