Incorporation of Mn/Zr/Ce into CaO-based sorbents for efficiency CO2 capture by sol–gel method

Calcium looping represents a high-temperature method designed to capture CO 2 , making it appropriate for CO 2 capture from flue gases post-combustion in power plants after combustion or for integration with fuel transformation techniques in pre-combustion CO 2 sequestration systems. This method employs solid sorbents of CaO sourced from natural limestone, leveraging the chemical interaction of CaO with CO 2 , which ultimately results in the formation of CaCO 3 , thereby facilitating effective CO 2 capture. In this research, multiple metal-incorporated CaO-based sorbents were produced through the sol–gel method. Notably, the CaO-based sorbent with a Ca/Ce doping ratio of 15 demonstrates exceptional CO 2 capture ability and stability, maintaining 13.20 mmol/g of CO 2 adsorption capacity after 20 carbonation/calcination cycles. Various characterization techniques, including X-ray diffraction (XRD), N 2 physisorption, scanning electron microscopy (SEM), high-angle annular dark field scanning transmission electron microscopy/energy dispersive spectroscopy (HAADF-STEM/EDS), temperature-programmed-desorption with CO 2 (CO 2 -TPD), Fourier Transform Infrared Spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS) are employed to demonstrate that the presence of nanoscale CeO 2 significantly enhanced the diffusion of CO 2 during the adsorption process.