ABSTRACT

Organic liquids are used to prepare the density medium to produce clean coal composites for coal quality and coking test evaluations during the coal exploration stage. Perchloroethylene (PCE) is commonly used as a density medium for this procedure; however, it has been shown before that PCE affects Gieseler Fluidity and Ruhr Dilatation indices of coal, as well as the quality of the resulting coke. It was also found that PCE has a negative effect on the coking properties of coals with a high inertinite content. This paper investigates the adsorption of PCE on various coal maceral surfaces using micro-Fourier Transform Infrared Spectroscopy (micro-FTIR) analysis to observe the changes in the absorbance of the double carbon bond C = C (C = C absorbance peak is used as a marker to indicate the presence of PCE) before and after PCE was applied onto their surfaces. The micro-FTIR mapping of absorbance intensity of the C = C bond on coal macerals showed an increasing trend in the presence of these bonds on the surface of all macerals with the time after exposure to the PCE. The SEM- energy-dispersive X-ray spectroscopy was used to analyze the composition of minerals associated with fusinite and semifusinite, as they were filling the pores in these macerals.

摘要

有机液体用于制备密度介质以生产清洁煤复合材料，用于煤炭勘探阶段的煤炭质量和焦化测试评估。四氯乙烯 (PCE) 通常用作此过程的密度介质；然而，之前已经表明 PCE 会影响煤的 Gieseler 流动性和鲁尔膨胀指数，以及所得焦炭的质量。还发现 PCE 对高惰性体含量煤的焦化性能有负面影响。本文采用微傅里叶变换红外光谱（micro-FTIR）分析研究了PCE在各种煤质表面的吸附情况，观察双碳键C=C（C=C的吸光度峰作为吸收峰）吸光度的变化。标记以指示 PCE 的存在）在 PCE 应用到其表面之前和之后。煤质材料上 C = C 键的吸光度强度的微 FTIR 映射显示，随着暴露于 PCE 后的时间，所有材料表面上这些键的存在呈增加趋势。SEM-能量色散 X 射线光谱用于分析与褐煤和半褐煤相关的矿物的组成，因为它们填充了这些微晶质中的孔隙。煤质材料上 C = C 键的吸光度强度的微 FTIR 映射显示，随着暴露于 PCE 后的时间，所有材料表面上这些键的存在呈增加趋势。SEM-能量色散 X 射线光谱用于分析与褐煤和半褐煤相关的矿物的组成，因为它们填充了这些微晶质中的孔隙。煤质材料上 C = C 键的吸光度强度的微 FTIR 映射显示，随着暴露于 PCE 后的时间，所有材料表面上这些键的存在呈增加趋势。SEM-能量色散 X 射线光谱用于分析与褐煤和半褐煤相关的矿物的组成，因为它们填充了这些微晶质中的孔隙。