Recently I used this equation, that I found from http://chemphys.space/thinks/ on Modelling Coke oxidation Kinetics. I got some interesting results, but I am not sure if my method is reliable. A drawback of my study is I performed the Modelling just using a single heating rate. However, I compared my results with Litrature values and it gives good approximation

I wrote down based on my analsysis I would love to hear comments

“A The proposed model demonstrates a significant advantage in its ability to integrate kinetic, diffusion, and structural factors, offering greater flexibility in analyzing coke oxidation kinetics. The results align well with the porosity characteristics of the studied samples. For catalysts with low coke content, the formation of relatively thin oxidized layers suggests diffusion plays a crucial role in controlling the reaction rate.

In this model, the reaction order n varies between 1.52–1.69 for C-2 and 1.33–1.41 for C-4, indicating an accelerating reaction at early stages. As the reaction progresses, a slower rate suggests diffusion becomes the dominant mechanism. This is further supported by the parameter m , which approaches -1, consistent with a transition to diffusion control.

A detailed analysis shows the model effectively captures both kinetic and diffusion behaviors, with the fitted parameters closely matching the D-3 model. However, unlike the pure diffusion Jander model ( n = -2/3 ), which shows weaker deceleration, the flexible model incorporates stronger acceleration and deceleration phases. This positions it as a modified Jander model that reflects both kinetic and diffusion influences.

While the Jander model emphasizes diffusion control, the flexible model highlights the interplay of chemical kinetics. Standard models like D1 and D2 lack deceleration terms, and D-4 includes only weak deceleration. The Jander model, although somewhat comparable, underrepresents the acceleration observed. Notably, none of the D1–D4 models account for the power-law behavior observed in this system ( n \approx 1.5 ), suggesting enhanced kinetics compared to classical diffusion-limited frameworks.

The derived non-linear approximation equation underscores the coexistence of kinetic and diffusion-controlled regimes, distinguishing this model from traditional approaches.”