摘要
研究了改性竹炭对银(Ⅰ)的吸附性能与机理。研究表明:竹炭对银(Ⅰ)有良好的吸附性能,平衡吸附量为45.2mg/g;竹炭对银的吸附动力学可用准一级动力学描述,表观吸附速率常数k298=3.29×10-4s-1,表观吸附活化能为:Ea=36.1kJ·mol-1;银在竹炭上的吸附符合Langmiur吸附等温线,吸附系数KL(298K)为24.427L.mg-1,饱和吸附量Q∞为62.7mg/g;温度升高,吸附量减小,表明吸附为放热过程;测得吸附热力学参数为:ΔH=-40.9kJ·mol-1,ΔG=-36.6kJ.mol-1,ΔS=-14.46J.K-1.mol-1。机理研究表明:竹炭对银(I)的吸附主要为还原吸附。
Adsorption behavior and mechanism of the modified bamboo - charcoal for Ag （I） was stud- ied. Experimental results show that bamboo - charcoal possess a good adsorption ability for Ag （ I）, adsorption capacity of equilibrium is 45.2 mg/g. The study on the kinetics shows that the adsorption kinetics of bamboo - charcoal for Ag（I） can be described by pseudo first - order kinetics. The adsorption apparent rate constant, k is equal to 3.29 × 10^-4s^-land activation energy ,Ea, is equal to 36.1 kJ · mol^-1 at the temperature of 298 K. Langmuir isotherm model is well obeyed. Adsorption coefficient, KL, is 24.427 L saturated adsorption capacity is 62.7 mg/g. The study on the thermodynamic shows that the adsorption process of bamboo -charcoal for Ag（I） is an exothermic process. The heat of adsorption （AH） is equal to - 40.9 kJ · mol^ -1 , entropy change （AS） is equal to - 14.46 J · K ^- 1 · mol^ - 1 and free energy change （AG） is equal to -36.6 kJ ·mol^-1. The studying mechanism shows that the reductive adsorption is a main adsorption.
出处
《贵金属》
CAS
CSCD
北大核心
2009年第2期22-25,共4页
Precious Metals
基金
浙江省教育厅科研计划项目(编号20051368)
丽水市科技局计划项目(2004465)
关键词
物理化学
改性竹炭
银(Ⅰ)
吸附性能参数
机理
physical chemistry
modified bamboo - charcoal
Ag （I）
capability parameter of adsorption
mechanism
