论文部分内容阅读
研究了初始pH对δ-MnO_2和水铁矿吸附As(Ⅴ)的动力学和热力学过程的影响。结果表明,不同初始pH对水铁矿去除As(Ⅴ)的效果影响不明显,而对δ-MnO_2去除As(Ⅴ)的效果影响较大。在相同的吸附时间下,初始pH=5.0时,As(Ⅴ)去除率最高,且随初始pH增大而降低。当初始pH=5.0时,δ-MnO_2和水铁矿对As(Ⅴ)的平衡吸附量总体上都大于初始pH=7.0或初始pH=9.0时。准二级动力学方程可以很好地描述δ-MnO_2和水铁矿吸附As(Ⅴ)的动力学过程。Freundlich方程拟合水铁矿和δ-MnO_2吸附As(Ⅴ)的过程优于Langmuir方程。
The effects of initial pH on the kinetics and thermodynamic processes of As (Ⅴ) adsorption on δ-MnO_2 and water iron ore were studied. The results showed that the effects of different initial pH on As (Ⅴ) removal were not obvious, but the effects of δ-MnO_2 removal on As (Ⅴ) were significant. Under the same adsorption time, the initial removal rate of As (V) was the highest at initial pH = 5.0 and decreased with the increase of initial pH. When the initial pH = 5.0, the equilibrium adsorption of As (Ⅴ) by δ-MnO 2 and ferrihydrite was more than that of initial pH = 7.0 or initial pH = 9.0. Quasi-second order kinetic equation can well describe the kinetics of As (Ⅴ) adsorption on δ-MnO_2 and water iron ore. Freundlich equation is better than Langmuir equation for the adsorption of As (Ⅴ) on ferrihydrite and δ-MnO_2.