The influence of mixed anionic composition of Mg–Al hydrotalcites on the thermal decomposition mechanism based on in situ study
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A series of Mg/Al hydrotalcites with tailored content of carbonate and nitrate anions was prepared using precipitation method. A part of the obtained materials was additionally crystallized in hydrothermal conditions. Different hydrotalcite phases or domains may co-exist within one sample obtained at controlled conditions. Decomposition mechanism studied in situ (DRIFT, XRD) was different for the samples with high concentration of interlayer nitrate anions than for carbonate-containing sample. TG-QMS study of hydrothermally treated samples provided more precise data for quantitative description of decomposition steps of Mg/Al hydrotalcites containing different mixtures of nitrate and carbonate anions.
KeywordsDecomposition mechanism Nitrate-containing hydrotalcite In situ XRD In situ DRIFT TG-QMS
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