Comparative study of three synthesis methods of wollastonite: synthesis, characterization and CO2 mineral sequestration efficiency

Abstract

Abstract Wollastonite CaSiO3 material type was successfully prepared by three conventional methods: sol-gel, hydrothermal, and solution combustion synthesis. These as-prepared materials were employed for the mineral sequestration of CO2, and the ability of all synthesized materials to fix CO2 has been discussed. The pre- and post-sequestration impact analysis was validated by various characterization techniques, including X-ray diffraction, SEM, TGA, and infrared spectroscopy. X-ray diffraction results showed that all synthesized materials consistently retained the structure of wollastonite, indicating that the synthesis method did not influence the phase purity. The study also demonstrated that the CaSiO3 material produced by the solution combustion method exhibited reduced crystallite size, elucidating its increased ability to bind CO2 during the sequestration process, as supported by the TGA results. These results suggest that particle size can affect carbonate CaCO3 formation. Finally, this work provides us with insights and suggestions about the use of solution combustion as a promising method to be applied for the synthesis of environment-oriented materials that may capture other atmospheric gases, not only CO2.