Thermal Behavior and CO2 Absorption of Li2-xNaxZrO3 Solid Solutions
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- 作者：Heriberto Pfeiffer ; Carmen Vá ; zquez ; Ví ; ctor H. Lara ; Pedro Bosch
- 刊名：Chemistry of Materials
- 出版年：2007
- 出版时间：February 20, 2007
- 年：2007
- 卷：19
- 期：4
- 页码：922 - 926
- 全文大小：102K
- 年卷期：v.19,no.4(February 20, 2007)
- ISSN：1520-5002
文摘
Lithium-sodium metazirconate solid solutions, Li2-xNaxZrO3, were tested as CO2 captors. The thermalanalyses of these materials showed that all the solid solutions present similar behaviors under air and N2.The samples lost weight due to two different processes, desorption of physisorbed water (~100 
C) anda decarbonation process (400-700 C). In fact, the quantities of water and CO2 desorbed increased as afunction of the sodium content. Thermal analyses into a CO2 flux showed that Li2-xNaxZr2O7 solid solutionspresent a high CO2 absorption. The solid solutions absorb CO2 between 400 and 600 C, but samplescontaining the sodium phase absorbed CO2 in two distinct steps. First, at low temperatures, there is aCO2 chemisorption, only at the surface of the particles, forming a carbonate shell. Later, when thetemperature reaches 400 C, or more, a second absorption process takes place. In this process lithiumand/or sodium atoms diffuse from the core of the particles to the surface, through an external carbonateshell. The differences observed in the CO2 sorption processes were explained with thermodynamic data.
C) anda decarbonation process (400-700 C). In fact, the quantities of water and CO2 desorbed increased as afunction of the sodium content. Thermal analyses into a CO2 flux showed that Li2-xNaxZr2O7 solid solutionspresent a high CO2 absorption. The solid solutions absorb CO2 between 400 and 600 C, but samplescontaining the sodium phase absorbed CO2 in two distinct steps. First, at low temperatures, there is aCO2 chemisorption, only at the surface of the particles, forming a carbonate shell. Later, when thetemperature reaches 400 C, or more, a second absorption process takes place. In this process lithiumand/or sodium atoms diffuse from the core of the particles to the surface, through an external carbonateshell. The differences observed in the CO2 sorption processes were explained with thermodynamic data.