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Abstract  

The gasification with carbon dioxide of residual carbons prepared from Timahdit and Tarfaya oil shale kerogens has been studied by thermal analysis techniques (TG and DTA) under heating rates varying from 5 to 48C min-1. The reactions obey first order kinetics. Activation energies have been calculated by several methods, such as Kissinger, Chen-Nuttall and Coats-Redfern methods, and are broadly comparable with literature data for similar carbons.

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Thermal decomposition kinetics of potassium iodate

Part I. The effect of particle size on the rate and kinetics of decomposition

Journal of Thermal Analysis and Calorimetry
Author: K. Muraleedharan

Introduction Information about the thermal stability of solid materials of all kinds is of great practical and technological importance [ 1 – 3 ]. Thermogravimetric analysis (TG) is usually adopted to study the kinetics of

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Summary The SCTA methods for the kinetic analysis of solid-state reactions have been reviewed. It has been shown that these methods present two important advantages with regards to the more conventional rising temperature experiments. Firstly, they have a higher resolution power for discriminating among the reaction kinetic models and, secondly, SCTA is a powerful tool for minimizing the influence of the experimental conditions on the forward reaction.

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Abstract  

The thermal decomposition reactions of calcitic dolomite were investigated. Simultaneous TG/DTG/DTA were applied under non-isothermal conditions. From the recorded curves, the activation energies, pre-exponential factors and thermodynamic parameters of activation were calculated for the two thermal decomposition steps.

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Abstract  

Slow pyrolysis of walnut shell which is a cheap and abundantly available solid waste was carried out using thermogravimetric analysis. The effects of raw material heating rate on the pyrolysis properties and kinetic parameters were investigated. A two-step consecutive reaction model were used to simulate the pyrolysis process. The kinetic parameters were established by using the pattern search method. Comparison between experimental data and the model prediction indicated that the two-step consecutive reaction model can better describe the slow pyrolysis of walnut shell as the formation of an intermediate during the pyrolysis process was taken into account.

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authors have emphasized the practical and theoretical importance of information on the kinetics and mechanism of solid state decompositions [ 15 – 20 ]. KIO 3 is a white crystalline powder having a molar mass of 214.001 g which decomposes around

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Journal of Thermal Analysis and Calorimetry
Authors: Vadim V. Krongauz, Yann-Per Lee and Anthony Bourassa

upon dehydrochlorination absorb light strongly above 320 nm [ 6 , 9 , 10 , 13 , 14 , 21 , 22 , 24 ], therefore, kinetics of PVC degradation can be monitored specifically using UV–visible spectroscopy. Some loss of conjugation may occur through

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Abstract  

Thermogravimetry (TG) and differential thermal analysis (DTA) were performed on the complexes with general formula (M(DEBT)n (where M =Fe, Co, Ni, Cu or Ru; n =2, or 3 and DEBT=N,N-diethyl-N'-benzoylthiourea). Derivative thermogravimetric (DTG) curves were also recorded in order to obtain decomposition data on the complexes. The complexes of Fe(III), Co(II), Ni(II), Cu(II) and Ru(III) displayed two- or three-stage decomposition patterns when heated in a dynamic nitrogen atmosphere. Mass loss considerations relating to the decomposition stages indicated the conversion of the complexes to the sulfides or to the corresponding metal alone (Cu, Ru, NiS, CoS or FeS). Mathematical analysis of the TG and DTG data showed that the order of reaction varied between 0.395 and 0.973. Kinetic parameters such as the decomposition energy, the entropy of activation and the pre-exponential factor are reported.

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