Li Ruiqing, Tang Yuegang, Song Xiaoxia, Wang Shaoqing, Che Qili, Chen Cong
College of Geoscience and Surveying Engineering, China University of Mining and Technology (Beijing), D11, Xueyuan Road, Beijing 100083, China.
Department of Geoscience and Engineering, Taiyuan University of Technology, No.79 Yingze West Street, Taiyuan 030024, China.
ACS Omega. 2024 Aug 5;9(32):34397-34412. doi: 10.1021/acsomega.4c01845. eCollection 2024 Aug 13.
A suite of coal samples near a diabase dike was collected to investigate the structural and functional group evolution of a series of carbon materials prepared from thermally altered coals, explore the influence of thermal metamorphism distance on the structure of coal and its carbon material products, and divide the thermally altered zones. Using Fourier transform infrared and Raman studies, it was found that after demineralization, the aromatic parameters and of the coal structure slightly increase, while the aliphatic parameters CH/CH and oxidation parameter slightly decrease, and the degree of order of the coal structure increases. Graphitization can greatly improve aromatic parameters, eliminate aliphatic structures, and enhance orderliness. However, after oxidation and reduction, the aromatic parameters and ordering degree of graphene decrease. Except for the sample closely attached to the dike, the coal-based graphene yield of the other samples first decreases and then stabilizes with the increase of distance from the dike, which is consistent with the trend of changes in the reflectance of raw coal. The thermally altered distance affects the structural changes of coal and carbon material products. The coal attached to the dike has been damaged and polluted, and the aromaticity and orderliness of the prepared carbon material products are relatively poor. The aromaticity and orderliness of coal-based products prepared from other thermally altered coals are relatively high and increase with the closer the thermally altered distance. Based on the characterized parameters of coal samples and products with distance from the dike, the sampling area is divided into four zones, including abnormally altered zone, normal altered zone, transition zone, and original coal zone. Among them, the yield and quality of coal-based graphene prepared from coal in the normal altered zone are the highest, an ideal raw material collection area for making coal-based graphene.
采集了一套靠近辉绿岩脉的煤样，以研究由热变质煤制备的一系列碳材料的结构和官能团演化，探讨热变质距离对煤及其碳材料产物结构的影响，并划分热变质带。通过傅里叶变换红外光谱和拉曼光谱研究发现，脱矿后煤结构的芳香族参数 和 略有增加，而脂肪族参数CH/CH和氧化参数 略有降低，煤结构的有序度增加。石墨化可大大提高芳香族参数，消除脂肪族结构，并增强有序性。然而，经过氧化和还原后，石墨烯的芳香族参数和有序度降低。除了紧靠矿脉的样品外，其他样品的煤基石墨烯产率随距矿脉距离的增加先降低后稳定，这与原煤反射率的变化趋势一致。热变质距离影响煤和碳材料产物的结构变化。紧靠矿脉的煤已受到破坏和污染，制备的碳材料产物的芳香性和有序性相对较差。由其他热变质煤制备的煤基产物的芳香性和有序性相对较高，并随着热变质距离越近而增加。根据煤样和产物随距矿脉距离的特征参数，将采样区域划分为四个带，包括异常变质带、正常变质带、过渡带和原煤带。其中，正常变质带的煤制备的煤基石墨烯产率和质量最高，是制备煤基石墨烯的理想原料采集区。
