pICNIK: A python package with isoconversional computations for non-isothermal kinetics

Isoconversional computations are widely-used methods to determine activation energies for thermally stimulated processes. pICNIK (python Isoconversional Computations for Non-Isothermal Kinetics) is an open-source module designed with the purpose of being a seed to a complete Python package to facilitate kinetic computations. It is object oriented with two classes: DataExtraction and ActivationEnergy. Five isoconversional methods were implemented: Friedmann's method, the Kissinger-AkahiraSunose method, Ozawa-Flynn-Wall method, Vyazovkin and advanced Vyazovkin. This module allows to compute the activation energy from thermogravimetric data in minutes and the results can be exported as spreadsheet format or comma separated values files instead of traditional tedious and time consuming data processing. The module was validated with simulated data and two study cases: vaporization of n-decane and the thermal degradation of polypropylene. Program summary Program Title: pICNIK CPC Library link to program files: https://doi .org /10 .17632 /dpwtnmjpj5 .1 Developer's repository link: https://github .com /ErickErock /pICNIK Code Ocean capsule: https://codeocean .com /capsule /0740039 Licensing provisions: MIT Programming language: Python Nature of problem: Numerical determination of the parameters of the Arrhenius function and the reaction model under the isoconversion hypothesis. Solution method: A Python module with implemented isoconversional methods. The algorithms implemented include several computations such as linear regressions, numerical integration and differentiation, and minimizing functions, all over several data sets. Additional comments including restrictions and unusual features: The initial data processing is focused on thermogravimetry and may not work for calculating conversion to other properties. However, the object oriented implementation allows to overcome this limitation easily. Methods for calculating the Arrhenius pre-exponential factor and the reaction model remain to be implemented. It is a small module conceived to be further developed by the community. Another limitation of the code is that it does not include a graphical interface.(C) 2022 Elsevier B.V. All rights reserved.