Hi, my dears.
I am stuying about effect of particles size in thermodynamics and kinetics and Reactivity a chemical reaction. what is the best way to adapt the model with experimental data?
DSC/TGA are adequate, since exhibit highest sensibility. Furthermore, so many mathemathical models has been employed by using TGA and DSC with a good fitting.
in my opinion you should be TGA/DSC but if you have the posibility It is better to use DSC and TGA as independent equipment as they improve the results obtained
Hi Man. For the kinetic study, precise measurement is an important issue if your sample decomposes in multiple stages/steps (with evolution of gasses). A transducer with higher sensitivity and accuracy will be required which simultaneously can measure any weight change (+/- 0.001 micro gram) and heat flow variation (milli watt or micro volt) of the sample. So you can observe reaction types and degradation behavior. In such case, DSC/TGA will be good (S-type thermocouple preferably) option. If the accuracy is not the concern then, you can use DTA/TGA [DTA also come with high sensitivity! but with the expense of the temperature range!].
In addition, please note : the crucible type; sample type; and transducer type are an issue. If your sample emitting reactive vapors then, they could damage the thermocouple wires unless you use hermetically sealed crucibles [please see attached images of damaged DSC/TGA (top) and DTA/TGA (bottom) transducers].
The model assumption will depend upon your heating pattern and other conditions (e.g: sweep gas velocity). You can find both isothermal kinetics and non-isothermal kinetics models in the recent literature. Also, there is a good software "AKTS thermokinetic, which can compute kinetic parameters with ease. Hope this help.
http://www.akts.com/akts-thermokinetics-tga-dsc-dta-tma-ftir-ms/download-tga-dsc-dta-tma-ms-ftir-akts-thermokinetics-software.html
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