摘要
本文主要针对ACF 与Au^(3+)的氧化还原体系,研究了不同品种ACF 的反应动力学特征以及制备工艺、氧化还原反应条件等与反应动力学的关系。结果表明,ACF与Au_-^(3+)的氧化还原反应动力学曲线可分为三个阶段,第一阶段反应液浓度线性迅速下降,第二阶段浓度与时间按一定函数关系变化,第三阶段反应基本上匀速进行。ACF 与Au_-^(3+)的反应速度虽比物理吸附慢,但反应2h 也已达～0.9的还原容量。ACF的制备工艺、反应液起始浓度对动力学规律影响不大。但反应液酸度增大,第二、第三阶段反应速度下降,反应温度上升,反应速度显著上升,反应温度变化还改变了第二阶段反应对Au_-^(3+)的级数。ACF 与Au_-^(3+)的氧化还原反应速度是多种活性中心同时起作用的结果。
The redox kinetics of activated carbon fibers (ACFs)reacting withAu_-^(3+) in various conditions are systematically investigated in this paper.The experimental results showed that the redox kinetic curves of ACFs canbe divided into three regions.In the first region,the concentration of Au_-^(3+)decreases very quickly.In the second region,there is a functional relati-onship between the concentration of Au_-^(3+) and time.In the third region,the concentration of Au_-^(3+) is linear with reaction time.Although the speedof redox reaction of ACF is slower than that of its physical adsorption,the redox capacity of ACF for Au_-^(3+) can reach approximately 900mg/g in2 hours.The conditions for preparing ACF and the innitial concentrationof Au_-^(3+) used in reaction do not obviously affect the kinetic characteristicof ACF.When the pH value of solution decreases,the reaction rate decr-eases after 1 hour.When the reaction temperature rises,the reaction rateincreases significantly.It should be pointed out that the change of reactiontemperature changes not only the constant of reaction rate in the thirdregion,but also the reaction order of the second region.It can be statedthat the redox kinetic of ACF may be comprised of the reaction kineticsof various centers together.
出处
《水处理技术》
CAS
CSCD
北大核心
1992年第1期39-45,共7页
Technology of Water Treatment
关键词
活性炭纤维
氧化还原
动力学
aotivated carbon fiber
redox reaction
kinetics
