New insights into stabilizing mechanism of Ca9Al6O18 stabilizing Ca-based sorbents for CO2 cyclic capture under mild conditions

Liang，Shuoyang1; Aihemaiti，Aikelaimu2; Cai，Yingying1; Su，Yiping1; Li，Rui1; Quan，Zewei3; Zhang，Zuotai1,4

2023-10-15

10.1016/j.cej.2023.145908

Chemical Engineering Journal   Impact Factor & Quartile

1385-8947

1873-3212

Developing calcium-based sorbents to capture and separate CO from high-temperature flue gas is currently a potential route to alleviate a series of environmental problems caused by excessive CO emissions. However, to date, there is a lack of in-depth understanding of the anti-deactivation mechanism of stable materials for CaO during the cyclic adsorption–desorption process, leading to difficulties in the rational design of Ca-based materials. Herein, a novel slow-precipitation strategy that enables the in-situ synthesis of CaAlO-stabilized Ca-based sorbents for cyclic carbon capture is exploited. The adsorption parameters are systematically optimized and the structural evolution and chemical property changes of CaAlO are monitored. Interestingly, we find that the deactivation of pure CaO mainly comes from the grain growth towards the bulk phase during the cyclic desorption process under mild calcination conditions, rather than the specific Tammann temperature of the substances. The introduction of CaAlO exhibits strong spatial confinement on the growth of CaO grains, as well as optimizing the internal pore structure of the particles, ensuring high stable CO capacity for long-term cycling under mild conditions, with a decay of 0.35% per cycle. This new understanding provides effective structural engineering strategies for designing applicable Ca-based carbon capture materials.

Ca9Al6O18 CO2 capture Stability mechanism Structural evolution

SCI

English

First ; Corresponding

Engineering

Engineering, Environmental ; Engineering, Chemical

WOS:001078847100001

ELSEVIER SCIENCE SA

ENGINEERING

2-s2.0-85170540803

Scopus

1.School of Environmental Science and Engineering,Southern University of Science and Technology,Shenzhen,518055,China
2.Xinjiang Technical Institute of Physics and Chemistry,Chinese Academy of Sciences,Urumqi,830011,China
3.Department of Chemistry,Southern University of Science and Technology,Shenzhen,518055,China
4.DeCarbon Technology (Shenzhen) Co.,Ltd,Guangdong Province,China

Liang，Shuoyang,Aihemaiti，Aikelaimu,Cai，Yingying,et al. New insights into stabilizing mechanism of Ca9Al6O18 stabilizing Ca-based sorbents for CO2 cyclic capture under mild conditions[J]. Chemical Engineering Journal,2023,474.

Liang，Shuoyang.,Aihemaiti，Aikelaimu.,Cai，Yingying.,Su，Yiping.,Li，Rui.,...&Zhang，Zuotai.(2023).New insights into stabilizing mechanism of Ca9Al6O18 stabilizing Ca-based sorbents for CO2 cyclic capture under mild conditions.Chemical Engineering Journal,474.

Liang，Shuoyang,et al."New insights into stabilizing mechanism of Ca9Al6O18 stabilizing Ca-based sorbents for CO2 cyclic capture under mild conditions".Chemical Engineering Journal 474(2023).