Experimental study on the precipitation of magnesite from thermally activated serpentine for CO2 sequestration

摘要: Abstract Mineral carbonation has the potential to store billions of tonnes CO2 safely and permanently. Enhancement kinetics formation magnesium carbonate from magnesium-bearing silicate minerals been subject numerous research studies. However, significant progress is yet be achieved. This is, in part, due a lack understanding mechanism magnesite presence additives under mineral conditions. In this work, an in-depth study was performed investigate precipitation during single step high pressure, temperature thermally activated serpentine aqueous bicarbonate solution. Slurry samples were obtained throughout duration experiments, enabling analysis both solid compositions over time, providing insight into reaction mechanism. Additionally, effect operating on various species examined. TGA-MS, combination with XRD SEM, confirmed hydromagnesite absence carbon dioxide (CO2) reactor heat up period, owing sodium (NaHCO3) carrier Hydromagnesite transformed rate phase transformation highly dependent temperature. At 185 °C all converted few minutes whereas at 120 °C even after 90 min remained reactor. PHREEQC thermodynamic software used assess observed species. The model prediction consistent experimental results work.