高比表面积PAN-ACF的吸附与孔结构解析  

ADSORPTION AND POROUS STRUCTURES OF HIGH-SURFACE AREA PAN-ACF

作　　者：陆安慧[1] 郑经堂[1] 王茂章[1] 

机构地区：[1]中国科学院山西煤炭化学研究所,山西太原030001

出　　处：《高分子材料科学与工程》2001年第5期62-66,共5页Polymer Materials Science & Engineering

基　　金：国家自然科学基金资助项目 ( 5 9672 0 2 5 )

摘　　要：以 KOH为活化剂制备了比表面积大于 2 0 0 0 m2 / g的高比表面积 PAN基活性炭毡 (ACF)。以液氮为吸附介质在 77.4 K测试 PAN- ACF吸附等温线 ,并对其孔结构进行了表征。采用 BET法计算比表面积 ,t- plot法、Horvath- Kawazoe、Dubinin- Radushkevich方程以及密度函数理论 (DFT)表征孔结构。研究表明即使比表面积超过 30 0 0 m2 / g时 ,PAN- ACF的孔分布仍然很窄 ,并且含有大量的分子筛型孔。以金子克美等人提出多段吸附机理为依据 ,采用 DR方程对 PAN- ACF三段吸附过程所对应的 E0 、x进行了计算。结果认为低压段的负偏离在一定程度上是由于吸附势较强的微孔与表面官能团共同作用的结果 ,并非完全由于活化扩散引起。以上分析方法的表征结果具有较好的一致性 ,为 PAN- ACF的吸附性能与孔结构提供了准确的信息。PAN-ACF (polyacrylonitrile activated carbon fiber) was activated by potassium hydroxide, which has narrow pore size distribution than activated carbon even though its specific surface area exceeds 2000 m 2/g. The porous structure parameters of PAN-ACF were investigated by nitrogen adsorption measurements. The specific surface area was calculated from the standard BET method, micropore surface area and volume were obtained from the t-plot and Horvath-Kawazoe equations. The pore size distribution was calculated by employing the regularization method according to Density Functional Theory (DFT) that is based on a molecular model for adsorption of nitrogen in porous solids. The average pore size and characteristic energy were calculated by Dubinin-Radushkevich equation according to multi-stage micropore filling mechanism. It was shown that all these analysis methods have a good agreement with one another.

关 键 词：高比表面积 PAN-ACF 活性炭纤维 孔结构 孔分布 吸附等温线 

分 类 号：TQ342.743[化学工程—化纤工业]