Recent advances in CO2 capture using MgO-based nanomaterials: A comprehensive review

Carbon dioxide (CO2) emissions have been a global challenge for a few decades and have been linked to an increase in the average Earth surface temperature. One of the captivating technologies to lower CO2 emissions is solid-state adsorbent technology. MgO-based adsorbents have a practical potential, mainly in the intermediate- temperature range since they are widely available, cheap, have high CO2 adsorption capacity, and only require low regeneration energy. Modifications of the MgO-based adsorbents could result in a better CO2 adsorption performance and a better cyclic stability, paving the way for practical applications. The key objective of this review is to provide the reader with detailed and comprehensive information on the recent research progress and development of utilizing MgO-based adsorbents for CO2 capture and mineralization. The CO2 adsorption capability of MgO-based adsorbents as well as their limitations will be discussed. Additionally, strategies to improve the performance of MgO-based adsorbents through, for instance, the promotion with alkali molten salts (AMS), creating MgO-nonmetallic composites, and amine-functionalization will be covered. The effects of the preparation methodology, operating conditions, in addition to adsorption mechanism, and regenerability of both low- temperature and intermediate-temperature MgO-based adsorbents are also evaluated. Furthermore, several insights and recommendations for future research works have been compiled.