In dta of kaolin clay, where do endothermic reaction happens?
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In the Differential Thermal Analysis (DTA) of kaolin clay, endothermic reactions occur during various processes such as dehydration, dehydroxylation, and crystallization of different phases. The endothermic peaks are observed during the transformation of kaolinite into metakaolinite, mullite, and cristobalite phases, as well as during the desorption of surface and interparticle water. These endothermic reactions are influenced by parameters like packing density, rate of heating, and the presence of specific elements like iron. The DTA analysis of kaolin clay reveals multiple endothermic peaks at different temperature ranges, indicating the complex thermal behavior of the clay mineral .
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| Endothermic reactions in DTA of kaolin clay occur in three regions, as indicated by the abstract: two in the low temperature range and one in the high temperature range. | |
18 Citations | Endothermic reactions in kaolin clay DTA occur at 75–115°C due to water desorption and at about 500°C due to dehydroxylation and CsBr thermal hydrolysis. |
27 Citations | Endothermic reactions in DTA of kaolin clay occur during the loss of physically adsorbed moisture at 120°C and the loss of constitutional -OH groups forming metakaolinite. |
3 Citations | In DTA of kaolin clay, endothermic reactions occur at around 880°C and 950°C due to the formation of mullite, hercynite, and γ-alumina under specific experimental conditions. |
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