Mechanochemically induced solid-state CO2 capture during the synthesis of SnO2 nanoparticles

Kozma, Gábor and Rónavári, Andrea and Kónya, Zoltán and Kukovecz, Ákos (2022) Mechanochemically induced solid-state CO2 capture during the synthesis of SnO2 nanoparticles. JOURNAL OF PHYSICS AND CHEMISTRY OF SOLIDS, 167. No. 110775. ISSN 0022-3697

Preview

Text 1-s2.0-S0022369722002037-main.pdf Available under License Creative Commons Attribution Non-commercial No Derivatives. Download (5MB) | Preview

Abstract

Mechanochemistry offers a versatile method to synthesize metal oxides by the reaction of the corresponding metal salt and Na2CO3, with CO2 as a by-product. It is possible to monitor the progress of the reaction and even calculate conversion values based on the measured pressure increase in the milling equipment. We studied the kinetics of tin oxide formation in the mechanochemical reaction between SnCl2 and Na2CO3. Our systematic experiments revealed unexpected complexity in the temporal pressure function depending on the exact composition of the reactant mixture: the pressure exhibited a clear local maximum, and pressure values even dropped close to their starting value by the end of the reaction when Na2CO3 was present in 100% excess. This anomaly can be explained by realizing that CO2 is captured as NaHCO3 in a process analogous with aqueous flue gas treatment, and it can also be released in the secondary reaction between unreacted SnCl2 and NaHCO3. Here we provide experimental evidence to support this hypothesis and to draw attention to the pitfalls of over-simplifying pressure-based conversion calculations in mechanochemical processing.

Actions (login required)

Edit Item