## 1 Introduction  
To reduce reliance on fossil fuels, there is a growing imperative to adopt a circular economy underpinned by bio-based materials and energy. This transition hinges on the sustainable sourcing of building blocks from non-fossil, abundant biogenic feedstocks--an approach that balances cost, environmental considerations, and resource availability. As a result, global interest in converting bio-based macromolecules into value-added chemicals, energy, and materials has intensified [1, 2, 3]. Among these candidates, chitin and chitosan stand out as promising natural polymers with distinct characteristics, poised to drive greener and more sustainable practices in various industrial and environmental applications. Chitin, a poly-N-acetyl-D-glucosamine, is one of the most abundant, readily accessible, and renewable natural polymers--second only to cellulose. It is primarily derived from the exoskeletons of crustaceans such as crabs and shrimp. Depending on its source, chitin can take three polymorphic forms--\(\alpha\), \(\beta\), and \(\gamma\)--each distinguished by variations in chain arrangement within their crystalline regions, resulting in distinct hydrogen bond networks. Of these, \(\alpha\)-chitin is the most abundant and stable, featuring the most intricate hydrogen bond network [4; 5]. On the other hand, chitosan, a deacetylated form of chitin, represents a polycationic polymer characterized by enhanced chemical versatility with a lower degree of acetylation [6]. It is defined as a linear copolymer featuring repeating units of d-glucosamine (deacetylated unit) and N-acetyl-d-glucosamine (acetylated unit), linked via \(\beta\) (1-4) glycosidic bonds [7]. Both chitin and chitosan are known to have favorable characteristics, including low cost, low toxicity, and widespread availability in addition to their excellent biocompatibility, biodegradability, and bioactivity. Particularly in the case of chitosan, its unique structure enables easier chemical modification [8]. However, from these compounds, only chitin is being isolated industrially. Chitin had a worldwide market valuation of approximately USD 1604.0 million in 2022 and is projected to achieve a value of USD 5026.4 million by the year 2032 [9]. Due to the inherent processability of chitin and chitosan, allowing their transformation into diverse formats such as sponges, gels, beads, scaffolds, micro and nanoparticles, these materials and their derivatives have been widely applied in various fields [10; 11; 12; 13; 14; 15; 16; 17; 18]. Carbonization (often referred to as pyrolysis) is an efficient and relatively straightforward strategy for transforming chitin and chitosan into value-added, nitrogen-doped carbon materials. Leveraging these biological macromolecules through well-designed carbonization processes is both desirable and feasible for producing functional carbon materials. A comprehensive understanding of carbonization and its associated decomposition mechanisms is pivotal for process design and optimization, as it offers in-depth insights into the breakdown pathways of these macromolecules [19]. This is because carbonization modeling employs mathematical frameworks to anticipate the yield and composition generated during thermal degradation. These models commonly integrate intricate chemical kinetics and thermodynamics to grasp the complex reaction pathways and rate dependencies [20]. In recent years, artificial neural network (ANN) approaches have contributed to modelling studies in various scientific and engineering domains, including pyrolysis and carbonization kinetics and thermodynamics [21; 22]. Artificial neural networks (ANNs), inspired by the human brain, comprise layers of interconnected neurons that process and transform data [23; 24]. Their ability to model complex data relationships makes them particularly useful in kinetic research [25]. In this study, ANN modeling was employed to validate and predict carbonization behavior thermodynamics of chitin and chitosan using thermogravimetric analysis (TGA).