Mechanisms and implications of the novel CAST model of coal graphitization

Authors

• WANG Shaoqing, College of Geoscience and Surveying Engineering, China University of Mining and Technology (Beijing), Beijing 100083, ChinaFollow
• ZHANG Jingzhe, College of Geoscience and Surveying Engineering, China University of Mining and Technology (Beijing), Beijing 100083, China
• ZHANG Xiaomei, School of Geology and Mining Engineering, Xinjiang University, Urumqi 830047, China
• WANG Xiaoshuai, School of Safety Engineering, Beijing Institute of Petrochemical Technology, Beijing 102617, China
• CHEN Hao, School of Geology and Mining Engineering, Xinjiang University, Urumqi 830047, China
• WANG Xiaoling, School of Geology and Mining Engineering, Xinjiang University, Urumqi 830047, China
• LI Wu, School of Resources and Geosciences, China University of Mining and Technology, Xuzhou 221116, China
• TANG Yuegang, College of Geoscience and Surveying Engineering, China University of Mining and Technology (Beijing), Beijing 100083, China

Abstract

Objective and Methods Coal graphitization is a multi-stage process with abrupt changes rather than linear evolution. So far, its inherent driving mechanisms have not yet been fully elucidated. Notably, twisted graphene was observed in the process of coal graphitization in 2025, providing a new opportunity to reveal the essence of this structural transformation. Results and Conclusions By combining previous research results, this study proposes a novel coal graphitization model that consists of condensation, alignment, stacking, and twisting (CAST). The four parts of the CAST model are organically integrated, collectively forming a continuous and dynamic evolutionary process. Most especially, no absolute boundaries exist among alignment, stacking, and twisting; instead, the three processes interact manually, jointly controlling and adjusting the progress and degree of coal graphitization. Theoretically, the novel CAST model clarifies the fundamental nature of coal graphitization as evolution from short-range disorder into long-range order. Therefore, this model provides a new perspective for gaining deep insights into the coal graphitization process and even enables the reconstruction of the underlying mechanisms of coalification. Practically, this novel model can direct the research focus toward the performance of coal as raw materials rather than merely as fuels, thus maximizing its value as “black gold”.

Keywords

coal graphitization, novel CAST model, twisting graphene, stacking, alignment

DOI

10.12363/issn.1001-1986.26.05.0284

Recommended Citation

WANG Shaoqing, ZHANG Jingzhe, ZHANG Xiaomei, et al. (2026) "Mechanisms and implications of the novel CAST model of coal graphitization," Coal Geology & Exploration: Vol. 54: Iss. 8, Article 4.
DOI: 10.12363/issn.1001-1986.26.05.0284
Available at: https://cge.researchcommons.org/journal/vol54/iss8/4

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