Dynamics of phase transitions in Na2TiO3 and its possible utilization as a CO2 sorbent: a critical analysis

Na-Based materials are emerging as promising high-temperature CO2 sorbents. In this work, we provide a detailed study on the synthesis of Na2TiO3 via a solid-state route using NaOH and TiO2 as starting reactants. The CO2 sorption properties of the synthesized Na2TiO3 were evaluated by thermogravimet...

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Bibliographic Details
Authors: Blanco, Maria Valeria, Abdala, Paula Macarena, Gennari, Fabiana Cristina, Cova, Federico Hector
Format: article
Status:Published version
Publication Date:2021
Country:Argentina
Institution:Consejo Nacional de Investigaciones Científicas y Técnicas
Repository:CONICET Digital (CONICET)
Language:English
OAI Identifier:oai:ri.conicet.gov.ar:11336/157644
Online Access:http://hdl.handle.net/11336/157644
Access Level:Open access
Keyword:CARBON DIOXIDE
CAPTURE
TRANSFORMATION
KINETIC
https://purl.org/becyt/ford/2.7
https://purl.org/becyt/ford/2
Description
Summary:Na-Based materials are emerging as promising high-temperature CO2 sorbents. In this work, we provide a detailed study on the synthesis of Na2TiO3 via a solid-state route using NaOH and TiO2 as starting reactants. The CO2 sorption properties of the synthesized Na2TiO3 were evaluated by thermogravimetric analysis. A subsequent comprehensive study on the complex reaction mechanism of Na2TiO3 at high temperatures under carbonation conditions was performed via real time in situ synchrotron X-ray diffraction analysis. In situ experiments performed under different conditions revealed the occurrence of thermally-driven phase transitions derived from the structural instability of the material at high temperatures. These reactions could be differentiated from carbonation processes, allowing the proposal of a reaction mechanism of the material as a CO2 sorbent. The obtained results can explain the abnormal dynamic thermogram displayed by Na2TiO3 in the presence of CO2 within a temperature range that is of interest for practical applications and serve as a basis for evaluating the feasibility of using this material in CO2 capture schemes.