银在活性炭纤维上的吸附及分布

REDUCTION ADSORPTION OF SILVER IONS AND THEIR DISTRIBUTION ON ACTIVATED CARBON FIBERS

采用水蒸气、氯化锌或磷酸活化等方法 ,通过控制不同的活化时间 ,制备了若干系列的沥青基活性炭纤维 ,研究了这些活性炭纤维对银离子的还原特性及金属银颗粒在活性炭纤维表面的分布形态。结果显示 ,纤维表面的金属银颗粒既有微米级粒子 ,也有纳米级粒子。随制备方法及溶液中银离子的初始浓度不同 ,还原吸附在纤维表面上的银离子的粒径不同。活性炭纤维的微孔丰富 ,石墨化程度低 ,还原吸附的银颗粒相对较细 ;石墨化程度高 ,表面化学反应性强 ,则还原吸附的银颗粒相对较粗。因此 ,通过调整纤维的制备方法及溶液的银离子浓度 。

Several kinds of pitch based activated carbon fibers (ACF) were prepared by steam activation, zinc chloride, or phosphoric acid activation. The reduction characteristics of silver ions on these ACF were studied, and the distribution of the reduced silver particles on them we re carefully observed by SEM. The results show that silver ions were reduced to metallic silver in micro- to nano-size. Moreover, the particle size of the silver adsorbed on ACF with a large microporosity but low degree of graphitization was less than that on those ACF with few micropores and a degree of graphitization. Therefore, the reduced silver particle size can be controlled to nanometre-scale by preparing ACF with the correct method as well as adjusting the initial concentration of silver ions in the solution.