活性碳纤维氧化还原特性的研究

STUDIES ON THE REDOX CHARACTERISTICS OF ACTIVATED CARBON FIBERS

本文选用一系列活性碳纤维(ACF)及不同氧化剂、还原剂,研究了ACF氧化还原特性,ACF结构、氧化剂结构、电极电位、实验条件以及制备工艺对ACF氧化还原性能的影响。氧化还原功能是ACF的基本特征之一,但随所用纤维原料和活化工艺的不同,其氧化还原能力有所不同。ACF对不同的氧化金属离子具有不同的氧化还原容量。与弱氧化性金属离子反应后的ACF还可进一步与强氧化性离子进行氧化还原反应。ACF的氧化还原容量与氧化性金属离子的电子结构无关,但与电极电位有关。ACF的氧化还原和吸附是两个相互独立而又有一定联系的过程。有利于氧化剂电极电位提高或还原剂ACF电极电位下降的因素(如浓度、pH值、负离子等)均有利于ACF氧化还原容量的提高。

In this paper, the redox characteristics of activated carbon fibers (ACF) and the effects of various factors on them are first investigated. The experimental results indicated that redox property is the essetial characteristic of ACF. However, depended on raw materials used and activation conditions, the redox abilities of different ACFs are somewhat different. Different with general reductors, the redox capacity of ACF is not a constant when oxidants are changed. The ACF which has been oxidized by weak oxidants can be further oxidized by strong oxidants. The increase of electrode potential of oxidants or decrease of electrode potential of ACF, caused by the change of concentration of metal ions, pH, or negative ions, is advantageous to the increase of the redox capacity of ACF. There is relation between the redox reaction and physical adsorption of ACF, but two processes are independent each other.