LAUSR

In the developing countries, power generation is likely to be primarily dependent on coal reserves in the coming years, thereby they face the scenario of upsurge in CO2 emissions. Carbon capture and storage (CCS) technologies are considered as a promising tool to mitigate CO2 emissions. In this work, direct mineral carbonation capacity of red mud (RM) has been studied which is one of the major solid waste produced from the non-ferrous industries in the country and that is largely land filled. Carbonation (dry and wet) studies were performed at low pressure (1-10 bar) conditions and at room temperature using a simple methodology in a batch reactor with pure CO2 gas. The dry route resulted in a maximum sequestration capacity of 5.16 g of CO2/kg of RM (10 bar and 3 h), whereas wet phase aqueous carbonation route yielded 20.09 g of CO2/kg of RM (liquid to solid (L/S) ratio - 0.6, 6 bar and 1 h). The carbonated samples were characterised using Fourier transform infrared (FT-IR), X-ray diffraction (XRD) and scanning electron microscope (SEM) analysis which evidenced the carbonation process. Thus, it can be concluded that the solid waste that generated in ample quantities pose to be a promising option towards climate change mitigation.