## 5 Conclusions  
This paper has presented a comparative kinetic analysis of the reactions for CaL, using both inert atmospheres/low CO\({}_{2}\) concentrations, as is typically performed in the literature, and the more rarely-used 100% CO\({}_{2}\) atmosphere. Additionally, it has discussed the validity of model-fitting methods in direct comparison with isoconversional and generalized methods, which has not been carried out previously. The experimental conditions, material properties, and the kinetic method have been found to strongly influence the kinetic parameters for both calcination and carbonation reactions. The main conclusions of the study are summarized as follows:  
For the calcination of synthesized CaCO\({}_{3}\) under N\({}_{2}\), an \(E_{a}\) of 204 and 233.6 kJ mol\({}^{-1}\) was obtained by model-fitting using the R2 geometric model and F1 model, respectively, which is consistent with the literature results. Calcination of the same material determined an average \(E_{a}\) of 164 kJ mol\({}^{-1}\) using an isoconversional method. The compensation effect also suggested that the best reaction model was R2. For calcination under CO\({}_{2}\), much higher values of \(E_{a}\) were obtained, i.e., 310 kJ mol\({}^{-1}\) with A4 (Avrami nucleation) and 1220 kJ mol\({}^{-1}\) with the F1 model, while isoconversional results ranged between 170 and 530 kJ mol\({}^{-1}\), which was attributed to the major morphological changes in the material under CO\({}_{2}\)[24]. From this study, we can conclude that a multiple heating-rate isoconversional method, such as Friedman, should first be carried out to arrive at non-mechanistic parameters. It will also show whether the kinetic parameters vary over the course of the reaction. Then, if the activation energy does not vary significantly under the experimental atmosphere (as is the case for calcination of CaCO\({}_{3}\) under inert gas), the compensation effect can be used to suggest a reaction model. As a means of comparison, a model-fitting method such as Coats-Redfern can be applied over the whole reaction to determine kinetic parameters based on several reaction models. This can be corroborated with master plots. Where applicable, the reaction model with the highest correlation coefficient can be compared with the results of the isoconversional analysis. If the same kinetic parameters are obtained, greater confidence can be placed in the results of the analysis. If the activation energy does vary significantly under the experimental atmosphere (as is the case for calcination of CaCO\({}_{3}\) under CO\({}_{2}\)), the Coats-Redfern method is not recommended, as the discrete values of kinetic parameters will not capture the variation in reaction kinetics. Additionally, the compensation effect cannot be applied, as it requires single values of kinetic parameters. In this case, an isoconversional analysis is the best option for obtaining kinetic parameters. The carbonation of synthesized CaO was modeled using an intrinsic chemical reaction rate model (for the kinetic control region) and apparent model (for the diffusion region), and subsequently compared with the literature. An activation energy of 17.45 kJ mol\({}^{-1}\) was obtained for the kinetic control region, and 59.95 kJ mol\({}^{-1}\) for the diffusion region. Lower values of \(E_{a}\) compared to the literature could be attributed to the incomplete carbonation conversion. For this synthesized material, the generalized models proved to model the two carbonation regions with high accuracy. For further studies, material characterization (i.e., scanning/transmission electron microscopy, physisorption characterization, and/or porosimetry) is recommended prior to selecting a generalized kinetic analysis method. Conceptualization, L.F.-H. and A.B. ; methodology, L.F.-H. and A.B. ; formal analysis, L.F.-H.; investigating, L.F.-H.; writing--original draft preparation, L.F.-H.; writing--review and editing, L.F.-H. and A.B. ; supervision, A.B. and S.W.D.