Wu Qiang, Sun Can, Zhu Zi-Zong, Wang Ying-Dong, Zhang Chong-Yuan
College of Materials Science and Engineering, Chongqing University, Chongqing 400044, China.
Materials (Basel). 2021 Jan 8;14(2):302. doi: 10.3390/ma14020302.
Modified cokes with improved resistance to CO reaction were produced from a high volatile coking coal (HVC) and different concentrations of boron carbide (BC) in a laboratory scale coking furnace. This paper focuses on modification mechanism about the influence of BC on coking behavior and chemical structure during HVC carbonization. The former was studied by using a thermo-gravimetric analyzer. For the latter, four semi-cokes prepared from carbonization tests for HVC with or without BC at 450 °C and 750 °C, respectively, were analyzed by using Fourier transform infrared spectrum and high-resolution transmission electron microscopy technologies. It was found that BC will retard extensive condensation and crosslinking reactions by reducing the amount of active oxygen obtained from thermally produced free radicals and increase secondary cracking reactions, resulting in increasing size of aromatic layer and anisotropic degree in coke structure, which eventually improves the coke quality.
在实验室规模的炼焦炉中，以高挥发分炼焦煤（HVC）和不同浓度的碳化硼（BC）制备了具有改进的抗CO反应性的改性焦炭。本文重点研究了BC对HVC碳化过程中焦化行为和化学结构影响的改性机理。前者通过热重分析仪进行研究。对于后者，分别使用傅里叶变换红外光谱和高分辨率透射电子显微镜技术分析了由HVC在450℃和750℃下碳化试验制备的四种半焦，其中碳化试验分别添加或未添加BC。研究发现，BC将通过减少热产生的自由基所获得的活性氧量来延缓广泛的缩合和交联反应，并增加二次裂解反应，从而导致焦炭结构中芳层尺寸和各向异性程度增加，最终提高焦炭质量。
