煤基多孔碳孔隙逾渗演化过程及结构特征

发布时间：2018-11-09 15:24

【摘要】：以煤焦颗粒和煤沥青为原料制备多孔碳材料,从多孔介质流体力学角度分析了坯料焙烧成孔过程及孔隙演化过程,结合分形理论和压汞实验结果,表征了多孔碳孔隙结构的非均质特征.结果表明,多孔碳坯料焙烧成孔的流体力学本质是挥发分在多孔介质中的流动,伴随焙烧各阶段经历了孔隙产生-逐步增多-局部连通-全部连通-网状联接的逾渗演化过程.各试样的孔隙度为29.67%~36.59%,比表面积为2.32~3.91 m~2/g,骨架面积分形维数为1.788~1.854,孔隙面积分形维数为1.638~1.732,体积分形维数为2.844~2.949,迂曲度分形维数为1.319~1.386,压汞实验中阈值压力为(8.94~13.08)×10~4 Pa,表现出典型的分形和逾渗特征.
[Abstract]:Porous carbon materials were prepared from coal char particles and coal pitch. The pore forming process and pore evolution process of billet roasting were analyzed from the point of view of fluid mechanics of porous media. The results of fractal theory and mercury injection experiment were combined. The heterogeneity of porous carbon pore structure was characterized. The results show that the hydrodynamic nature of porous carbon billet roasting is the flow of volatile matter in porous media, and the percolation evolution process of pore generation, gradual increase, local connectivity, total connectivity and network connection is experienced during each stage of roasting. The porosity of each sample is 29.67 ~ 36.59, the specific surface area is 2.32 ~ 3.91 mg / g, the fractal dimension of skeleton area is 1.788 ~ (1.854), the fractal dimension of pore area is 1.638 ~ 1.732, and the fractal dimension of volume is 2.844 ~ (2.949). The fractal dimension of tortuosity is 1.319 ~ 1.386, and the threshold pressure of (8.94 ~ 13.08) 脳 10 ~ (4) Pa, shows typical fractal and percolation characteristics.
【作者单位】：中国矿业大学化工学院;徐州工程学院机电学院;中国矿业大学电力学院;
【基金】：国家自然科学基金资助项目(编号:51406225);国家自然科学基金创新研究群体科学基金资助项目(编号:51221462) 江苏省自然科学基金资助项目(编号:BK20130222) 江苏省产学研联合创新-前瞻性项目资助(编号:BY2015023-03) 江苏省博士后基金资助项目(编号:1302035C)
【分类号】：TQ127.11

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