2D‐Layered Ni–MgO–Al₂O₃ Nanosheets for Integrated Capture and Methanation of CO₂

Abstract

CO2 capture is an enabling technology for carbon conversion and storage; however, the high costs of the process have hindered its large‐scale application so far. Therefore, new approaches for carbon abatement, particularly from diluted sources, are urgently needed. Herein, based on the adsorption and catalysis bifunctionality of 2D‐layered Ni–O–Al2O3 nanosheets, a two‐step “capture and methanation” process is reported for the removal and utilization of CO2, with no additional energy input for desorption being required. Continuous and nearly 100 % capture of CO2 was demonstrated at low temperatures (≤250 °C) and prolonged cycles. At isothermal conditions, the material could be fully regenerated with the production of methane, showing considerably higher time efficiency than temperature‐swing and pressure‐swing technologies. This strategy may pave a new way for CO2 reduction, providing a scalable connection between the power grid and the gas grid when H2 is used.

The Role of Alkali and Alkaline Earth Metals in the CO2 Methanation Reaction and the Combined Capture and Methanation of CO2

“…Finally, Zhou et al [121] prepared a 2D-layered Ni/MgO-Al 2 O 3 material to be used during the integrated CO 2 capture and methanation ( Figure 13). The layered oxides resulted after calcination and reduction of the initial hydrotalcite (or layered double hydroxide) precursors, which were in turn prepared via the coprecipitation method.…”

Recent advances in integrated CO2capture and utilization: a review

“…Integrating CO2 capture and methanation (ICCU-methanation) has advantages in improving the process and energy efficiency. 42 and Jo et al 43 . The match of temperature between adsorption and methanation is also very important for ICCU.…”

“…Excessive CO2 adsorption could produce more carbonates than active formate species which are mainly responsible for the formation of methane. For example, Zhou et al 42 applied a fast adsorption and methanation process (25 s and 35 s for adsorption and methanation) and reported a nearly 100% CO2 conversion. This was due to the formation of dominant formate species and few carbonates.…”

Carbon Capture From Flue Gas and the Atmosphere: A Perspective

“…Besides the liquid amine processes, the solid adsorbent catalyst-based CO 2 capture-conversion processes using dual function materials (DFMs) consisting of the methanation catalyst (e.g., Ru and Ni) and CO 2 adsorbent (e.g., CaO, Na 2 O, and MgO) on a support have also been studied at mild conditions (200-350°C and 1 atm) (Duyar et al, 2015;Duyar et al, 2016;Miguel et al, 2017;Wang S. et al, 2017;Wang et al, 2018;Arellano-Treviño et al, 2019;Zhou et al, 2020).Those DFMs exhibit stable performance in CO 2 capture and conversion to synthetic CH 4 for over 50 cycles. No loss in CO 2 capture capacity and Ru dispersion was observed (Wang et al, 2018).…”

“…No loss in CO 2 capture capacity and Ru dispersion was observed (Wang et al, 2018). Over the 2D-layered Ni-MgO-Al 2 O 3 nanosheets, continuous and nearly 100% capture of CO 2 during prolonged cycling tests was achieved at temperatures below 250°C (Zhou et al, 2020). Its hydrogen efficiency reached 60% for CO 2 conversion to CH 4 , making the process attractive for large CO 2 emission sources.…”