摘要
研究了高岭土界面亚铁吸附与邻硝基苯酚(2-nitrophenol,2-NP)还原转化的交互作用。考察了反应pH值、界面吸附铁密度、反应温度(T)对2-NP的还原动力学的影响。结果表明,吸附态Fe(II)为2-NP还原转化的关键物种,高龄土界面Fe(II)吸附能明显提高还原反应的反应速率。2-NP的还原转化速率常数(k)随着反应pH值的升高、吸附铁密度的增加、反应温度的升高而增大,lnk与pH、吸附铁密度、1/T都具有明显的线性关系。2-NP还原转化的活化能为87.15 kJ·mol-1,吸附反应的活化能为18.5 kJ·mol-1。该研究可为土壤矿物界面物理化学与氧化还原的交互反应过程研究提供借鉴。
The contamination of nitroaromatic compounds in soils is a significant environmental concern. This study demonstrated the successful reductive degradation of 2-nitrophenol （2-NP） in the presence of Fe（Ⅱ） species adsorbed onto kaoline, one of the abundant minerals in soils, Fe（Ⅱ） adsorption onto kaoline surfaces was studied in view of its high reactivity towards the aqueous reductive transformation of 2-NP. Kinetic measurements indicated that rates of 2-nitrophenol reduction were highly sensitive to pH, the density of adsorbed Fe（Ⅱ） and reaction temperature. The increase in pH, the density of absorbed Fe（Ⅱ） or reaction temperature resulted in an enhanced reaction rate of 2-nitrophenol reduction. According to the Arrhenius equation, the activation energies of the reductive transformation of 2-nitrophenol and Fe（Ⅱ） adsorption onto kaoline were 87.15 kJ·mol^-1 and 18.5kJ·mol^-1, respectively. These findings improve our general understanding of the interactive reactions, and more importantly, show implications for us to understand more complicated heterogeneous reactions in soils.
出处
《生态环境》
CSCD
北大核心
2008年第6期2177-2182,共6页
Ecology and Environmnet
基金
国家自然科学基金项目(20577007)
关键词
交互反应
高岭土
2-NP
FE^2+
还原转化
interactive reaction
kaoline
2-nitrophenol
Fe^2＋
reductive transformation
