Sodium Hypochlorite (NaClO) oxidation has been reported as a promising method for coal seam permeability enhancement and extracting valuable hydrocarbons from coal. Different coal macerals, particularly vitrinite and inertinite behave differently in NaClO with varying reaction extent exhibited. The reasons for variability are not completely understood. This study aims to reveal the controlling factors of different coal maceral oxidation by comparing their molecular structures and pore characterization. A Permian coal from Bowen Basin, Australia, was collected and separated into vitrinite-rich concentrate (bright coal) and inertinite-rich concentrate (dull coal). Their reaction phenomena with NaClO are examined and their molecular structures and pore structures are compared with multiple techniques. The vitrinite-rich and inertinite-rich concentrates share similar organic molecular structures although there is some marginal difference with the bright coal being slightly more aliphatic with higher oxygen content. By contrast, their pore structures are significantly different such that the dull coal is more porous with higher content of mesopores and better connectivity. For coal powders vitrinite is more reactive than inertinite and yet for coal particles inertinite is more reactive. Given that inertinite is more porous, these results suggest that the porosity of the inertinite is the key property making the inertinite more reactive. Therefore, it is proposed that the different extent of oxidation for different macerals from isorank coal is controlled primarily by the difference in their porosity rather than molecular structures.

次氯酸钠（NaClO）氧化已被报道为提高煤层渗透性和从煤中提取有价值的碳氢化合物的一种有前途的方法。在NaClO中不同的煤化学成分，特别是镜质体和惰质体表现出不同的反应程度。可变性的原因尚未完全了解。本研究旨在通过比较其分子结构和孔隙特征，揭示不同煤层氧化的控制因素。收集了来自澳大利亚Bowen盆地的二叠纪煤，并将其分为富含镜质石的精矿（亮煤）和富含惰质石的精矿（暗煤）。研究了它们与NaClO的反应现象，并通过多种技术比较了它们的分子结构和孔结构。富含镜质体和富含惰质体的精矿具有相似的有机分子结构，尽管光亮煤的脂肪族含量略高，且氧含量较高，但存在一些边际差异。相比之下，它们的孔结构明显不同，以致于钝煤具有更高的中孔含量和更好的连通性，因而孔隙更大。对于煤粉，镜质石比惰质石更具活性，而对于煤颗粒，惰质石更具活性。考虑到惰质岩的多孔性，这些结果表明，惰质岩的孔隙度是使惰质岩更具反应性的关键特性。因此，有人提出，与异等级煤相比，不同成分的氧化程度不同主要是由其孔隙率的差异而不是分子结构来控制的。