The oxidation of coal
The oxidation of coal
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DOI：
10.1002/jctb.5000680701
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发表时间：
1949-07
影响因子：
3.4
通讯作者：
R. Jones;D. Townend
中科院分区：
文献类型：
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作者：
R. Jones;D. Townend
本文提请注意在煤的风化中过氧化体或活性氧所起的作用的重要性;已与煤和碳进行了比较研究，这表明表现出类似的。最初的反应似乎涉及化学吸附，在水的存在下，随后形成煤-或碳-氧-水复合物。煤的正常固有薄片含量是其内表面的函数;这是含c的煤的最小值。89%的碳。煤中过氧含量随含碳量的变化规律相似。过氧络合物在高于约70 ℃时明显不稳定，该温度长期以来被认为是煤自燃的临界温度。在其下方，复合物容易形成并保持相对稳定，很少有氧气进入煤物质;硫化量也非常小。少量的气态氧化产物主要由一氧化碳和少量的CO2组成。高于7 ° D C。该复合物开始分解，尽管对于碳来说，直到350 ° C才完全被破坏。已经到达。70 ° C以上氧化。煤的氧含量、煤的一般硫化作用和气态氧化产物的产率的大幅度增加也是一个显著的特征;二氧化碳也超过了一氧化物。这些观察结果通过50 ° C和90 ° C下煤-氧反应的重量天平得到了证实。在这两个温度下的压力变化也是不同的;而在50 ℃下记录到压力逐渐下降，在90 ° C下。压力出现暂时上升。在高于和低于该临界温度的行为中的显著差异对于煤和碳都是共同的，并且鉴于碳形成碳-氧-水复合物的能力，很明显，对于两种材料，总氧化由复合物的分解速率控制。最重要的是水存在的必要性;事实上，现在对C。J. Baker和H. B。Baker在1887 - 88年提出的一种新的碳氧化方法，证明了干碳即使在红热下也不容易被氧化。
The paper draws attention to the importance of the part played by peroxidic bodies or active oxygen in the weathering of coal; comparative investigations have been made with both coal and carbon, which are shown to behave similarly. The initial reaction appears to involve chemisorption, which, in the presence of water, is followed by the formation of a coal-or carbon-oxygen-water complex. The normal inherent wafer content of coals is a function of their internal surface; this is a minimum with coals containing c. 89 per cent carbon. The peroxygen content of coals shows a similar variation with carbon content. The peroxygen complex is markedly unstable above approximately 70° c., a temperature long known to be critical in regard to spontaneous combustion of coal. Below it the complex is formed easily and remains relatively stable, little oxygen entering the coal substance; also the amount of ulmification remains very small. The small quantity of gaseous oxidation products consists chiefly of carbon monoxide with a less amount of CO2. Above 7°D c. the complex starts to break down, although with carbon it does not appear to be completely destroyed until 350°c. is reached. Oxidation above 70°C. is also marked by a big increase in the oxygen content of a coal, its general ulmification and in the yield of gaseous oxidation products; also carbon dioxide then preponderates over the monoxide. These observations were substantiated by means of gravimetric balances for the coal-oxygen reaction at 50° and 90° c. The pressure changes at these two temperatures were also different; whereas a gradual fall in pressure was recorded at 50° c., at 90° c. a temporary rise in pressure occurred. The remarkable difference in the behaviour above and below this critical temperature is common to both coal and carbon, and in view of the ability of carbon to form a carbon-oxygen-water complex, it is evident that with both materials the overall oxidation is controlled by the rate of breakdown of the complex. Of paramount importance is the necessity for the presence of water; indeed, an explanation is now forthcoming of the classical experiments of C. J. Baker and H. B. Baker in 1887-88, which demonstrated that dry carbon cannot be readily oxidized even at red heat.