Development of DFMs

The following content is copied from this reference (https://doi.org/10.1016/j.ccst.2022.100052):

“DFMs play a critical role in the ICCC process, which combines the CO₂ decarbonation reaction and CO₂ conversion reaction and thus determines the performance and efficiency of the process. Therefore, great efforts have been paid to the development of DFMs. Different CO₂ sorbents and catalysts have been coupled together to prepare DFMs. Alkali metal oxides or carbonates such as CaO, MgO, SrO, Na₂O, Na₂CO₃, and K₂CO₃ serve as the CO₂ sorbent in the DFMs. Transition metals such as Ru, Rh, and Ni are used as the catalyst in the DFMs. However, a noticeable decline has been observed in CO₂ capture and conversion performance of the DFMs due to sintering and/or coking, as discussed in Section 3. Metal oxides with high Tammann temperatures (e.g., Al₂O₃, ZrO_2, and CeO₂ (Arellano-Treviño et al., 2019b; Bermejo-López et al., 2019b; Hu and Urakawa, 2018; Zhou et al., 2020)), as well as promoters (e.g., K and Na (Al-Mamoori et al., 2018; Xu et al., 2021)), have been used to modify the DFMs to improve the performance of DFMs. However, to the best of our knowledge, such a deactivation still occurs during cyclic operations. Therefore, to obtain DFMs with remarkable CO₂ uptake capacity, excellent catalytic activity, high product selectivity, and good cyclic stability, more work should be conducted on the rational design of DFMs, such as the utilization of strong metal-support interaction and the formation of bimetallic catalyst. Except for the sorbents using alkali metal oxides or carbonates and catalysts using metallic metals, a data-driven method by combining computational chemistry and machine learning is highly recommended to identify other desired sorbents and catalysts from tens of thousands of candidates. Moreover, the performance of the ICCC process was primarily assessed using powdery DFMs in the TGA or fixed bed reactors. But for the industrial applications of the ICCC process in the future, the fluidized bed reactor is a better choice. In this case, powdery materials are no longer suitable for fluidized bed reactors. So it is essential to explore pelletization approaches to synthesize DFMs particles with strong mechanical strength. At the same time, the cost of the pelletization approaches should be taken into account as well as their potential to scale up.”