pH对δ-MnO_2和水铁矿吸附As(Ⅴ)的影响  

Effect of pH on As(Ⅴ) adsorption by δ-MnO_2 and ferrihydrite

作　　者：李晓月[1] 王华伟[1] 孙英杰[1] 郑志远[2] 汉红燕[3] 

机构地区：[1]青岛理工大学环境与市政工程学院,山东青岛266033 [2]青岛理工大学土木工程学院,山东青岛266033 [3]青岛市环境保护局,山东青岛266033

出　　处：《环境污染与防治》2017年第2期175-178,共4页Environmental Pollution & Control

基　　金：山东省自然科学基金青年基金资助项目(No.ZR2016DQ08)

摘　　要：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。Effects of initial pH on As（ V ） adsorption kinetics and isotherm curve by δ-MnOa and ferrihydrite were conducted. Results indicated that initial pH had little effect on As（ V ） removal by ferrihydrite, but relatively great effect by δ-MnO2. As（ V ） removal efficiency was highest when initial pH= 5.0 at the same adsorption time. Be sides,As（ V ） removal efficiency dropped down as initial pH increased. Equilibrium adsorption quantity was higher when initial pH=5.0 than when initial pH= 7.0 or 9.0. The adsorption kinetic process on As（ V ） by δ-MnO2 or ferri- hydrite could well be described by the pseudo-second-order equation. The adsorption isotherm curve was better fitted for Freundlich equation than LanGmuir eouation.

关 键 词：δ-MnO2水铁矿pH AS(V) 

分 类 号：X703[环境科学与工程—环境工程]