Electrolytic methods to promote carbon dioxide sequestration by mineral carbonation

A novel method for promote carbon sequestration by mineral carbonation using electrolysis was studied in this article, which used the self-made electrolytic reactor to electrolyze NaCl solution, and serpentine as the source of Mg2+ to absorb CO2 in the simulating flue gas were introduced the electrolysis of NaCl was conducted in a divided electrolytic cell by a salt bridge with graphite as anode and cathode. The acid solution produced from anode was used to dissolve Mg2+ from serpentine at 363 K, and the basic solution produced from cathode was used to adsorb CO2 in simulation smoke, then these two solutions were mixed when current was 0.5 A and it was not depend on the concentration of NaCl solution obviously. The acid solution produced from anode can dissolve Mg2+ from serpentine, which dissolve capacity was almost the same with the same pH of HCl solution; therefore, it can replace HCl solution to dissolve serpentine without separation. The basic solution produced from cathode after adsorbing CO2 of simulation smoke can react with Mg2+ to from solid deposition at 358 K. The deposition was found mainly pure basic magnesium carbonate (Mg-5(CO3)(4)(OH)(2)center dot 4H(2)O) by XRD examination, which both environment benign and economically. Its excellent method for use in the regions where have acid solution produced from anode can be well utilized and basic solution from cathode may make further reaction without separation, moreover, the reactions can be processed at low pressure and relative low temperature, and pure H-2, Cl-2 and pure solid products can be obtained in the process, which makes the mineral carbonation process more economical.