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Abstract  

The thermal decomposition of the polypropylene and liquid paraffin mixtures with inorganic additives was studied in dynamic conditions. Thus, typical thermal analyses were carried out and thermal decomposition of samples in a specially designed apparatus was also processed. One can observe for samples of sufficiently low mass that thermal analysis allows clear distinction of samples that contain and do not contain liquid paraffin, respectively. Moreover, it is possible to separate two stages of the decomposition process. The relationship between the logarithm of conversion degree and temperature (so called three-parameter model) was used for the description of these processes. Relations between coefficients in three-parameter equation in micro-scale, and characteristic temperatures of thermal decomposition in laboratory scale were observed in spite of meaningful differences in the course of the processes.

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Journal of Thermal Analysis and Calorimetry
Authors: Veronika Vágvölgyi, Lisa Daniel, Caroline Pinto, J. Kristóf, R. Frost, and Erzsébet Horváth

Abstract  

The thermal decomposition of the clay mineral attapulgite has been studied using a combination of dynamic and controlled rate thermal analysis. In the dynamic experiment two dehydration steps are observed over the 20–114 and 114–201°C temperature range. In the dynamic experiment three dehydroxylation steps are observed over the temperature ranges 201–337, 337–638 and 638–982°C. The CRTA technology enables the separation of the thermal decomposition steps. Calculations show the amount of water in the attapulgite mineral is variable. Dehydration in the CRTA experiment occurs as quasi-isothermal equilibria. Dehydroxylation occurs as a series of non-isothermal decomposition steps. CRTA technology offers better resolution and a more detailed interpretation of the decomposition processes of a clay mineral such as attapulgite via approaching equilibrium conditions of decomposition through the elimination of the slow transfer of heat to the sample as a controlling parameter on the process of decomposition. Constant-rate decomposition processes of non-isothermal nature reveal partial collapse of the layers of attapulgite as the attapulgite is converted to an anhydride.

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Introduction The European Symposium on Thermal Analysis and Calorimetry (ESTAC) owes it origins to a decision by the UK Thermal Methods Group (TMG) to hold an international meeting on thermal analysis in the UK, following a

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study is to investigate the kinetics of the dehydroxylation of Algerian kaolinite through thermal analysis. Materials and experimental procedure Raw kaolinite (DD3, from Guelma, Algeria) was used in this investigation. More

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Abstract  

Organic matter associated with rocks was examined by means of thermal analysis using a new methodology in oxidising conditions. This procedure has been named “Oxyreactive Thermal Analysis” (OTA). The OTA results presented in this study characterise samples from sedimentary rock complexes in terms of their age, and of variations in the associated organic matter arising from different precursors and degree of severity of subsequent transformation processes to which it has been subjected. The results of the OTA method make it possible to estimate the temperature of maturation, to describe the process of evolution of the organic matter, and to distinguish genetic features of its carbonised and metamorphosed products.

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Journal of Thermal Analysis and Calorimetry
Authors: Maurizio Ferrante, Paolo Trentini, Fausto Croce, Morena Petrini, and Giuseppe Spoto

their study, have shown the same complex polymeric structures. The thermal analysis is a very useful technique in order to check the quality of different commercial products and to perform a comparative analysis. In particular, it is very useful

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interesting to apply these techniques to the identification and quantification of compounds and mixtures in chemical processes. On the other hand, a number of analytic methods are used for thermal analysis [ 5 ], including thermogravimetry

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Abstract  

The solubility isotherm of the system Eu2O3-SeO2-H2O was studied at 100C. Certain amounts of the obtained selenites (normal and acid) were subjected to thermal analysis. The intermediate phases were isolated and chemical and X-ray phase analysis was made. The scheme of thermal decomposition was determined.

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Abstract  

Thermal analysis of Israeli phosphorites by TG/DTA methods complemented with titrimetric and thermogaschromatographic determination of the evolved gases was performed in an oxygen and inert gas flow. The amounts and temperature intervals of H2O, CO2 and SO2 evolvement were established.

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Journal of Thermal Analysis and Calorimetry
Authors: Marcelo Mendes Viana, Maura Berger Maltez Melchert, Leandro Cardoso de Morais, Pedro Maurício Buchler, and Jo Dweck

production of coke adsorbents from sewage sludge combine these two purposes of environmental research [ 15 ]. A methodology is presented in this article to quantitatively estimate the produced sewage sludge coke, by using thermal analysis. The sewage

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