Evolution Mechanism of Macromolecular Structure in Coal during Heat Treatment: Based on FTIR and XRD In Situ Analysis Techniques

Figure 3

Infrared spectrogram of five coal samples. Attribution of characteristic peak positions is descried as follows: (1) aromatic hydrocarbon CH; (2) aliphatic CH₂ or CH₃ stretching vibration; (3) aromatic carbonyl/carboxyl groups (C=O); (4) aromatic nucleus (C=C); (5) phenolic deformation C─O─C (stretching); (6) aromatic CH (out-plane bending).