Structural Model Construction and Optimal Characterization of High-Volatile Bituminous Coal Molecules.

Area of Science:

• Geochemistry
• Organic Chemistry
• Materials Science

Background:

• Understanding the molecular structure of coal is crucial for its efficient utilization.
• Bituminous coal's complex structure influences its physical and chemical properties.

Purpose of the Study:

• To determine the detailed molecular structure of bituminous coal from the Baozigou Coal Mine.
• To construct an average macromolecular structure model and investigate its aggregated behavior.

Main Methods:

• Elemental analysis
• ¹³C nuclear magnetic resonance (NMR)
• X-ray photoelectron spectroscopy (XPS)
• Fourier transform infrared (FTIR) spectroscopy
• Molecular dynamics simulation

Main Results:

• Identified primary two- and three-ring aromatic structures and methyl, ethyl, and naphthenic aliphatic side chains.
• Constructed an average macromolecular model (C₁₆₉H₁₂₈O₁₀N₂S) with a molecular weight of 2378.
• Simulations showed twisted bonds and π-π interactions, with energy decreasing significantly upon optimization; aggregated models revealed distorted structures.

Conclusions:

• The study provides a detailed molecular and aggregated structural model for Baozigou bituminous coal.
• This model serves as a theoretical foundation for developing optimal surfactants for coal applications.