Screening and Characterization of Ternary Oxides for High-Temperature Carbon Capture

Abstract

Carbon capture and storage (CCS) is increasingly being accepted as a necessary component of any effort to mitigate the impact of anthropogenic climate change, as it is both a relatively mature and easily implemented technology. High-temperature CO 2 absorption looping is a promising process that offers a much lower energy penalty than the current state of the art amine scrubbing techniques, but more effective materials are required for widespread implementation. This work describes the experimental characterisation and CO 2 absorption properties of several new ternary transition metal oxides predicted by high-throughput DFT screening. One material reported here, Li 5 SbO 5 , displays reversible CO 2 sorption, and maintains ∼72 % of its theoretical capacity out to 25 cycles. The results in this work are used to discuss major influences on CO 2 absorption capacity and rate, including the role of the crystal structure, the transition metal, the alkali or alkaline earth metal, and the competing roles of thermodynamics and kinetics. Notably, this work shows the extent and rate to which ternary metal oxides carbonate is driven primarily by the identity of the alkali or alkaline earth ion and the nature of the crystal structure, whereas the identity of the e transition ion carries little influence in the systems studied here.

Synthetic solid oxide sorbents for CO2 capture: state-of-the art and future perspectives

“…Ternary oxide phases containing Li and transition metals have also been prepared, primarily by solid-state synthesis, as CO 2 sorbents. [125][126][127][128][129][130] A summary of the carbonation chemistries of these Li-transition metal oxides is presented in Table 5. Amongst these ternary oxides, Li 6 CoO 4 has both the highest stoichiometric CO 2 uptake and the highest experimental CO 2 uptake of 80.0 and 74.5 wt.%, respectively, 127 whereas Li 6 WO 6 nanowires showed the ability to rapidly capture CO 2 at ambient temperatures in the presence of moisture (relative humidity = 58 ± 3%).…”

“…19 Similarly, the computational screening by Gaultois et al found Li 5 SbO 5 as a potential sorbent, which showed satisfactory CO 2 uptake performance (~72% of its stoichiometric uptake capacity) over 25 cycles. 130 At present, there remains a gap between the thermochemical material properties that are computationally predicted and those experimentally measured. Such gap could potentially hinder the effective of the computational approaches to discover and develop new sorbents.…”

CO2 capture using solid sorbents: Fundamental aspects, mechanistic insights and recent advances

“…There are some studies of Li-based materials which suggest that the availability of multiple carbonation reaction pathways with similar energies can lead to a stabilization of the CO2 uptake capacity over multiple cycles, as changes in morphology and surface area are Another recently reported material, Li5SbO5, was observed to maintain a relatively stable CO2 uptake of 80 wt% over multiple cycles [499]. Further analysis of the product formation as a function of cycle number by XRD revealed that initially the reaction proceeded as predicted,…”

New Catalytic and Sorption Bifunctional Li6CoO4 Material for Carbon Monoxide Oxidation and Subsequent Chemisorption

“…Calcium oxide (CaO), lithium silicates (Li 4 SiO 4 and Li 8 SiO 6 ), ,− and alkaline zirconates (Li 2 ZrO 3 and Na 2 ZrO 3 ) ,− were proposed as CO 2 chemisorbents at high temperatures, presenting different advantages and disadvantages. However, in recent years, new alkaline ceramics have been proposed for this application. − Some examples include lithium cuprate (Li 2 CuO 2 ), − as well as lithium and sodium ferrites (Li 5 FeO 4 , LiFeO 2 , and NaFeO 2 ), ,− which have shown great properties, mainly due to the redox capacity of the transition metals present in these samples. Moreover, these alkaline ceramics have shown different catalytic abilities, − including the synergic CO oxidation and CO 2 chemisorption. , This double process would be of interest for industrial applications where CO and/or CO 2 must be trapped.…”

“…On the other hand, Li 6 CoO 4 has been deeply analyzed as a possible lithium-ion cathode material, , and it was recently proposed as a CO 2 capture material. , These reports showed that Li 6 CoO 4 can trap large amounts of CO 2 , in comparison with other ceramics, over a wide temperature range. Moreover, one of the secondary phases presented during the carbonation reaction was LiCoO 2 , which means that cobalt is partially oxidized during the carbonation process from Co 2+ to Co 3+ .…”