Quantitative Characterization and Macromolecular Structure Model Construction of Taixi Anthracite as Raw Material of Coal-Based Activated Carbon

Abstract

In this article, we mainly completed the related research on the establishment of organic macromolecular structure model of Taixi anthracite as coal-based activated carbon precursor. The understanding of coal macromolecular structure is of great significance to clean and materialized utilization of coal. In this paper, the aromatic structure, aliphatic structure and heteroatomic structure of Taixi anthracite were characterized by ¹³C-NMR, FTIR and XPS. The macromolecular structure of coal was modeled by linking polycyclic aromatic hydrocarbons through bridging bonds (–CH₂–, –CH–) and attaching oxygen/nitrogen functional groups. The molecular formula was determined to be C₂₂₂H₁₁₉NO₁₁. The ¹³C-NMR simulation curve of the two-dimensional macromolecular model was in good agreement with the experimental curve. Through molecular mechanics (MM) and molecular dynamics (MD) optimization, the bond elastic energy (E_B) and Van der Waals energy (E_VAN) decrease greatly, which mainly lead to the acquisition of the three-dimensional energy minimum conformation. In addition, the density simulation result of 3D structural model with periodic boundary conditions is 1.37 g/cm³. This is close to the measured density, which confirm that the 3D structure is reasonable. The establishment of this model helps to further understand Taixi anthracite, which is beneficial to guide the preparation of activated carbon from Taixi anthracite.