水蒸气活化液化木基活性碳纤维孔隙结构表征

Pore Structural Characterization of Liquefied Wood-based Activated Carbon Fiber by Water Steam Activation

研究了不同活化温度、不同活化时间下,水蒸气活化液化木基活性碳纤维的孔隙结构特性。-196℃氮气吸附脱附等温线用于检测孔隙结构。结果表明,随着活化温度或活化时间的增加,比表面积和烧失率增加,且在较高活化温度时增加率更高。随着活化时间延长,活化温度为750~800℃时总孔容和微孔孔容增加明显,中孔孔容在650~700℃活化初期和750~800℃活化后期均有所发展。各活化温度下,随着活化时间的延长,在微孔范围内孔径分布均有所扩大且趋向多样化。

The pore structural characteristics of the liquefied wood-based activated carbon fiber with water steam activations at different activation temperatures and activation times are studied. The pore structure is assessed by N2 adsorption/desorption isotherms at -196℃. The specific surface area and the burnt-off are increased with the increase of the activation temperature or the activation time, and are more dependent on the activation time when activated at higher temperatures. With increasing activation time, the total pore volume and micropore volume are increased more significantly when activated at 750℃ and 800℃, while the mesopore volume is high at the early stage of activations at 650℃ and 700℃ then is decreased, and does not develop until the later stage of activations at 750℃ and 800℃. The pore size distribution analysis indicates that the micropore size distribution becomes increasingly heterogeneous with increasing the activation time under all activation temperatures.