Isothermal pyrolysis of Naomaohu coal was carried out at a temperature ranging from 500 to 750 C using a fixed-bed reactor. The product distributions of gas and tar were measured using gas chromatography and gas chromatography-mass spectrometry, respectively. In addition, the effect of temperature on carbon structure evolution characteristics of semicokes were also investigated. The results showed that the gas yield increased dramatically from 61.50 to 168.43 mL g when the temperature increased from 500 to 750 C. CO and C-C gases were mainly produced during the primary pyrolysis of lower energy chemical bonds at a lower temperature. The tar content ranges from 18.6 to 20.5 wt%, with the highest at 550 C. At higher temperature, the branched hydrocarbon and phenols can react with each other to produce more polycyclic aromatic hydrocarbon. The infrared absorption peak area associated with the functional groups of O-H, C-H, CO and C-O initially increased with temperature from 500 to 550 C before sharply decreasing as the temperature increased from 550 to 750 C. At a higher pyrolysis temperature, the carbon content of the semicoke and the degree of graphite crystalline structure increased. Semicoke produced at higher pyrolysis temperatures exhibited better crystalline behavior and more pores and cracks.

中文翻译：

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淖毛湖煤等温热解半焦产物分布及碳结构演化特征

采用固定床反应器在 500 至 750 C 的温度范围内对淖毛湖煤进行等温热解。分别使用气相色谱法和气相色谱-质谱法测量气体和焦油的产物分布。此外，还研究了温度对半焦碳结构演化特征的影响。结果表明，当温度从500℃升高到750℃时，气体产率从61.50mL·g急剧增加到168.43mL·g。CO和CC气体主要是在较低温度下低能化学键的初级热解过程中产生的。焦油含量为18.6～20.5wt%，最高温度为550℃。在较高温度下，支链烃与酚类可发生反应，生成更多的多环芳烃。与OH、CH、CO和CO官能团相关的红外吸收峰面积最初随着温度从500℃升高到550℃而增加，然后随着温度从550℃升高到750℃而急剧减小。在较高的热解温度下，半焦和石墨的结晶结构程度增加。在较高热解温度下生产的半焦表现出更好的结晶行为以及更多的孔隙和裂纹。