Modified Hydrotalcites Application as Precursors for (Na,K)Mg/Al Spinel-Type Compounds Formation
Journal of Thermal Analysis and Calorimetry 2014
Agne Bankauskaite, Kestutis Baltakys, Gundars Mežinskis

In this work, a synthesis route of (Na,K)Mg/Al spinel-type compounds, which combines hydrothermal synthesis at low temperatures (\200 C) and solid-state sintering ([800 C) methods, is presented. It was examined that NaOH and KOH additives induce the reaction between initial Mg and Al components and the formation of hydrotalcite during hydrothermal treatment. It should be noted that after 1 h of calcination of synthetic precursors at 850 oC spinel-type compounds are formed only in the samples with alkali addition. Meanwhile in the pure system only traces of the mentioned compounds are observed at 900 oC. Moreover, the increase in solid-state sintering temperature and duration lead to the higher-crystallinity (Na,K)MgAl2O4 spinel-type compounds. It should be noted that textural properties of formed (Na,K)Mg/Al spinel-type compounds depend on the chemical composition of precursors. The synthetic and calcined products are characterised by XRD, STA, FT-IR analyses and BET method.


Keywords
Hydrothermal treatment . Hydrotalcite, Solid-state sintering Precursors , Mg/Al spinel-type compounds
DOI
10.1007/s10973-014-3737-z
Hyperlink
http://link.springer.com/article/10.1007/s10973-014-3737-z

Bankauskaite, A., Baltakys, K., Mežinskis, G. Modified Hydrotalcites Application as Precursors for (Na,K)Mg/Al Spinel-Type Compounds Formation. Journal of Thermal Analysis and Calorimetry, 2014, Vol.115, Iss.2, pp.711-718. ISSN 1388-6150. e-ISSN 1588-2926. Available from: doi:10.1007/s10973-014-3737-z

Publication language
English (en)
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