Four coal samples from Jharia basin, India are treated with nitric acid in glacial acetic acid and aqueous media to find out the chemical, petrographic and spatial structure of the organic mass by X-ray diffraction (XRD) and Fourier Transform Infrared Spectroscopy (FTIR) techniques. X-ray parameters of coal like interlayer spacing (d₀₀₂), crystallite size (L_c), aroamticity (f_a), average number of aromatic layers (N_c), and coal rank (I₂₆/I₂₀) have been determined using profile-fitting software. Considerable variation is observed in treated coals in comparison to the demineralized coals. The d₀₀₂ values of treated coals have increased in both the media showing increase in disordering of organic moieties. A linear relationship has been observed between d₀₀₂ values with the volatile matter of the coals. Similarly, the d₀₀₂ values show linear relationship with C_dmf contents for demineralized as well as for the treated coals in both the media. The L_c and N_c values have decreased in treated coals corresponding to demineralized coals. The present study shows that nitration in both the media is capable of removing the aliphatic side chains from the coals and aromaticity (f_a) increases with increase in rank and shows a linear relationship with the vitrinite reflectance. The corresponding I₂₆/I₂₀ values are least for treated coals in glacial acetic acid medium followed by raw and then to treated coals in aqueous medium. FTIR studies show that coal arenes of the raw coals are converted into nitro-arenes in structurally modified coals (SMCs) in both the media, the corresponding bands at 1550–1490 and 1355–1315 cm⁻¹ respectively. FTIR study confirms that nitration is the predominant phenomenon, though, oxidation and nitration phenomena takes place simultaneously during treatment with nitric acid to form SMCs. In comparison to raw coals, the SMCs show higher aromaticity and may be easily converted to coal derived products like activated carbon and specialty carbon materials.

用硝酸在冰醋酸和水介质中的硝酸处理了来自印度贾哈里亚盆地的四个煤样品，以通过X射线衍射（XRD）和傅里叶变换红外光谱（FTIR）找出有机物的化学，岩石学和空间结构技术。确定了煤的X射线参数，例如层间间距（d ₀₀₂），微晶尺寸（L _c），芳香性（f _a），平均芳香层数（N _c）和煤级（I ₂₆ / I ₂₀）。使用轮廓拟合软件。与脱矿煤相比，在处理过的煤中观察到了相当大的变化。该d在两种介质中，处理过的煤的₀₀₂值均增加，表明有机部分的无序性增加。已经观察到d ₀₀₂值与煤的挥发性物质之间存在线性关系。同样，d ₀₀₂值在两种介质中均显示与软化以及经处理的煤的C _dmf含量呈线性关系。与软化煤相对应的已处理煤的L _c和N _c值已降低。本研究表明，两种介质中的硝化作用均能去除煤中的脂肪族侧链和芳香性（f _a）随着等级的增加而增加，并且与镜质体反射率呈线性关系。对于在冰醋酸介质中处理过的煤，其后的原煤，然后对于在水性介质中处理过的煤，其相应的I ₂₆ / I ₂₀值最小。FTIR研究表明，在两种介质中，结构煤（SMC）中原煤的煤芳烃均转化为硝基芳烃，相应的频带为1550–1490和1355–1315 cm ^-1分别。FTIR研究证实硝化是主要现象，但是在硝酸处理过程中会同时发生氧化和硝化现象，从而形成SMC。与原煤相比，SMC具有更高的芳香性，并且很容易转化为煤衍生产品，例如活性炭和特种碳材料。