Thermogravimetric Analysis of Bamboo with Technical Difficulties

Bamboo, like other plant-based biomass materials, is primarily composed of three main components: cellulose, hemicellulose, and lignin. Figure 2 presents the thermogravimetric analysis (TGA) curve of bamboo powder, illustrating its thermal decomposition behavior under different carbonization temperatures. At 500°C, 750°C, and 1,000°C, the carbonization yields were recorded as 18.00%, 14.38%, and 9.28%, respectively. The carbonization process can be divided into four distinct stages: dehydration, holding, pyrolysis, and slow weight loss. (1) **Dehydration Stage**: This stage occurs between 50°C and 150°C and involves the removal of free water and physically adsorbed moisture from the bamboo structure. The weight loss during this phase was approximately 4.68%, with a noticeable peak observed at around 80°C, indicating the most rapid water evaporation at this temperature. (2) **Holding Stage**: Spanning from 80°C to 240°C, this phase is characterized by the release of molecularly bound water from cellulose and lignin. During this time, the TGA curve remains relatively stable, showing minimal weight loss compared to the following stages. (3) **Pyrolysis Stage**: From 240°C to 400°C, the thermal decomposition of cellulose and lignin begins. The breaking of C–O and C–C bonds leads to the release of gases such as CO₂ and CO. This stage exhibits the most significant weight loss, with a total reduction of 68.60% between the transition temperature of 255°C and the maximum pyrolysis temperature of 360°C for lignin. (4) **Slow Weight Loss Stage**: Above 400°C, the formation of aromatic polycyclic compounds starts, marking the final stage of the carbonization process. This phase is also referred to as the calcination stage, where the remaining organic matter is further decomposed, leaving behind a carbon-rich residue. Understanding these stages is crucial for optimizing the carbonization process and enhancing the properties of bamboo-derived biochar.