New approach to consecutive CO oxidation and CO2 chemisorption using Li2CuO2 ceramics modified with Na- and K-molten salts
Por:
Hernandez-Castillo, Susana, Martinez-Hernandez, Hector, Mendoza-Nieto, J. Arturo
Publicada:
1 ago 2021
Ahead of Print:
1 may 2021
Resumen:
To analyze for the first time the effect of alkali carbonate addition to
lithium cuprate during the consecutive process of carbon monoxide (CO)
oxidation and subsequent carbon dioxide (CO2) capture, a series of
X-containing Li2CuO2 (X = Na and/or K) materials were prepared by
mechanically adding different mixtures of sodium and potassium
carbonates to lithium cuprate. According to results, the presence of
carbonate allowed the improvement of both the CO conversion and the CO2
chemisorption in a moderate temperature range, between 400 and 650
degrees C. According to the reaction mechanism proposed in this work,
this enhancement was produced due to the formation of a new phase
between the mechanically added Na and K carbonates and the Li carbonate
produced during the CO2 capture on the ceramic surface. The composition
of this phase changes depending on the temperature used and the amount
of lithium carbonate formed on the surface. Once the newly formed
carbonate phase melts, the diffusion of both reactants (CO and O-2) is
enhanced towards the bulk material, promoting the oxidation of CO and
later CO2 capture. Another benefit was detected on the ratio between CO2
captured and released. According to this parameter, the samples modified
with a single carbonate, Na- or K-Li2CuO2 samples, showed a high
tendency to capture the CO2 formed during the CO oxidation, allowing the
simultaneous elimination of two toxic and harmful gases, CO and CO2. The
results are promising, considering that at an industrial level, two
different materials are required for this process: a heterogeneous
catalyst followed by a chemical adsorbent, which can be replaced with a
single modified-Li2CuO2 material studied in this work.
Filiaciones:
Hernandez-Castillo, Susana:
Mendoza-Nieto, JA (Corresponding Author), Univ Nacl Autonoma Mexico, Fac Quim, Dept Fisicoquim, Lab 111, Ciudad Univ, Ciudad De Mexico 04510, DF, Mexico. Hernandez-Castillo, Susana
Martinez-Hernandez, Hector:
Mendoza-Nieto, JA (Corresponding Author), Univ Nacl Autonoma Mexico, Fac Quim, Dept Fisicoquim, Lab 111, Ciudad Univ, Ciudad De Mexico 04510, DF, Mexico. Hernandez-Castillo, Susana
Mendoza-Nieto, J. Arturo:
Mendoza-Nieto, JA (Corresponding Author), Univ Nacl Autonoma Mexico, Fac Quim, Dept Fisicoquim, Lab 111, Ciudad Univ, Ciudad De Mexico 04510, DF, Mexico. Hernandez-Castillo, Susana
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