Wang Lijuan, Lu Anhuai, Wang Changqiu, Zheng Xishen, Zhao Dongjun, Liu Rui
School of Earth and Space Sciences, Peking University, Beijing 100871, China.
J Colloid Interface Sci. 2006 Mar 15;295(2):436-9. doi: 10.1016/j.jcis.2005.08.055. Epub 2005 Oct 5.
Nano-fibriform silica was extracted from chrysotile by the acid-leaching method. The acid-leached residue of chrysotile has been studied by TEM, XRD, FT-IR, and thermal analysis techniques, etc. When the magnesium leaching degree (MLD) is over 90%, the nano-fibriform silica consists of hydrous silicon dioxide (above 90%) with small amount of magnesium trapped inside the SiO network. The amount of hydroxyl on surface of nano-fibriform silica is 6 unit nm(-2). This value is between the values of fumed and precipitated silica. This study shows that nano-fibriform silica is a kind of amorphous matter with a high special surface area (368 m2/g), a high adsorption (330 cm3/g), and a larger pore volume (0.51 cm3/g). The diameter of a single silica fiber is 20-30 nm. The nitrogen adsorption isotherm is similar to Type IV curve. The nano-fibriform silica is one of mesopores materials.
采用酸浸法从温石棉中提取纳米纤维状二氧化硅。利用透射电子显微镜（TEM）、X射线衍射仪（XRD）、傅里叶变换红外光谱仪（FT-IR）和热分析技术等对温石棉的酸浸残渣进行了研究。当镁浸出率（MLD）超过90%时，纳米纤维状二氧化硅由水合二氧化硅（含量超过90%）组成，在SiO网络内部捕获了少量镁。纳米纤维状二氧化硅表面的羟基数量为6个/nm²。该值介于气相法白炭黑和沉淀法白炭黑的值之间。本研究表明，纳米纤维状二氧化硅是一种具有高比表面积（368 m²/g）、高吸附量（330 cm³/g）和较大孔体积（0.51 cm³/g）的无定形物质。单根二氧化硅纤维的直径为20 - 30 nm。氮气吸附等温线类似于Ⅳ型曲线。纳米纤维状二氧化硅是介孔材料之一。
