Chemical and petrographic characterization of Zonguldak coal and its derived coal tar

The growing interest in the non-energy applications of coal in recent years has highlighted the potential of the Zonguldak coal basin as a feedstock for advanced carbon materials, particularly carbon fibers, providing advantages in terms of both spinning stability and high carbon yield. This study provides a comprehensive evaluation of the feasibility of utilizing Zonguldak coal and its derived coal tar as precursors for carbon fiber production, focusing on chemical composition, petrographic characteristics, and molecular structural evolution. The geological properties of the coal, rank variability, maceral composition, and beneficiation behavior are examined alongside coal tar chemistry and pitch-based carbon fiber production technologies; additionally, aromaticity, heteroatom content, and molecular structure characteristics are analyzed using both experimental findings and literature data. The results indicate that, due to its relatively high rank, suitable vitrinite content, and aromatic-rich tar fractions, Zonguldak coal exhibits promising characteristics as a precursor for advanced carbon-based materials. Compared with tars derived from lower-rank coals, these tars exhibit higher aromatic condensation, lower oxygen functionality, and a more favorable fraction distribution, providing advantages in terms of spinning stability and high carbon yield. Overall, the findings demonstrate that Zonguldak coal can be regarded as a strategic raw material for carbon fiber production, reducing dependence on imported petroleum-derived precursors while enhancing the added value of domestic resources.