竹炭微观结构的电子显微学研究

Electron microscopy study on microstructure of bamboo charcoal

利用扫描电镜(SEM)和高分辨透射电镜(HRTEM)分别对炭化、活化和石墨化处理后的竹炭进行观察与分析。结果表明竹炭基本保留了竹材的微观形态;炭化后其细胞壁组织上的微孔导致竹炭比表面积变大;随着炭化温度的提高竹炭中的孔隙率增加。竹炭经KOH活化后孔隙率显著提高,炭化温度低于600℃时所得竹炭活化后的比表面积大于高温炭化的活化竹炭,且中孔比例较高,而高温炭化的竹炭活化后微孔的比例明显增高。石墨化处理后的竹炭中出现大量微晶区,且不同微晶区的晶格条纹具有较好的平行度,这表明竹炭是一种易石墨化炭。

Bamboo charcoals prepared by different methods were studied by scanning electron microscopy（SEM） and high resolution transmission electron microscopy（HRTEM）.The results showed that bamboo charcoal could keep the original morpha of bamboo.The high specific surface area of bamboo charcoal was due to the mini-pores on the cell wall.Increasing the carbonization temperatures would increase the number of mini-pores.The porosity in the bamboo charcoals activated by KOH was remarkably increased.The specific surface area of activated bamboo charcoals with carbonization temperature lower than 600 ℃ was higher than that of activated bamboo charcoals prepared at higher carbonization temperature.Bamboo charcoal was a kind of graphitizable carbon material because the lattice fringes of microcrystalline domain of graphite in bamboo charcoals were with better parallelism.