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Acquiring an effective CaO-based CO₂ sorbent and achieving selective methanation of CO₂.

ABSTRACT: CO₂ capture, utilization, and storage are promising strategies to solving the problems of superfluous CO₂ or energy shortage. Here, mechanochemical reduction of CO₂ by a MgH₂/CaH₂ mixture was first performed, by which we achieve selective methanation of CO₂ and acquire an effective CaO-based CO₂ sorbent, simultaneously. The selectivity of methanation is near 100% and the yield of CH₄ reaches 30%. Four MgO and carbon-doped CaO-based CO₂ sorbents (MgO/CaO/C, MgO/2CaO/C, MgO/4CaO/C, and MgO/8CaO/C) were formed as solid products in these reactions. Among them, the MgO/4CaO/C sorbent shows high initial adsorption amount of 59.3 wt% and low average activity loss of 1.6% after 30 cycles. This work provides a novel, well-scalable, and sustainable approach to prepare an efficient inert additive-including CaO-based CO₂ sorbent and selectively convert CO₂ to CH₄ at the same time.

SUBMITTER: Ping C

PROVIDER: S-EPMC9054523 | biostudies-literature | 2020 Jun

REPOSITORIES: biostudies-literature

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Acquiring an effective CaO-based CO2 sorbent and achieving selective methanation of CO2.

Ping Chao C Feng Bao-Qi BQ Teng Yun-Lei YL Chen Han-Qing HQ Liu Si-Li SL Tai Yun-Long YL Liu Hao-Nan HN Dong Bao-Xia BX

RSC advances 20200605 36

CO2 capture, utilization, and storage are promising strategies to solving the problems of superfluous CO2 or energy shortage. Here, mechanochemical reduction of CO2 by a MgH2/CaH2 mixture was first performed, by which we achieve selective methanation of CO2 and acquire an effective CaO-based CO2 sorbent, simultaneously. The selectivity of methanation is near 100% and the yield of CH4 reaches 30%. Four MgO and ...[more]

PMID: 35518741

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