不同原料基活性碳纤维的结构及吸附特征研究

采用Ｘ－射线衍射，ＳＥＭ和ＢＥＴ比表面分析仪，探讨了不同原料（聚丙烯脂，聚乙烯醇，粘胶，天然纤维和沥青碳纤维）基活性碳纤维的结构和吸附特征。实验表明，所制备的活性碳纤维都具有大致相同的乱层石墨结构，其微晶参数Ｌｃ，Ｌａ和ｄ值分别为１．０～１．２，３．９～５．０，０．３８～０．４０ｎｍ，微晶尺寸越小，活性碳纤维（ＡＣＦ）的比表面积越大。ＡＣＦｓ的表面形态都不相同且基本保持着原料纤维的形态，ＡＣＦｓ对有机物苯的吸附量与纤维的比表面积成正比，但对Ａｇ~＋的吸附则与比表面积关系不大，此外，吸附还原在ＡＣＦ上的Ａｇ粒形态与ＡＣＦ的表面形态有关，ＮＡＣＦ和ＡＡＣＦ上吸附的Ａｇ粒尺寸小于３００ｎｍ。

STUDY ON THE STRUCTURE AND ADSORPTION CHARACTERISTICS OF ACTIVATED CARBON FIBERS FROM DIFFERENT PRECURSOR FIBERS

The structure and adsorption characteristic of ACFs from different precursor fibers,such as polyacrylonitrile fiber, polyvinyl alcohol fiber,cellulose fiber, nature fiber (sisal) and pitch- based carbon fiber was investigated by means of X- ray diffraction,SEM and BET measuremerits.It was found that the ACFs prepared at the same carbonization and activation conditions had roughly the same turbostratic structure.The apparent parameters of crystallite size,L_c,L_a and d_(002)are 1.0～1.2,3.9～5.0 and 0.38～0.4nm respectively. The larger the crystallite size,the less the specific surface area of ACF was.The surface morphology of five kinds of ACFs was different and evolved from the morphology of precursor fibers. The adsorption amount of benzene onto ACFs was in direct proportion to the specific surface area of ACFs.But no relationship between adsorption amount of Ag￣+ and specific surface area was found. The morphology of Ag particles reduced was affected by the surface morphology of ACFs.The diameter of Ag particle reduced on NACF and AACF is less than 300nm.