Zn(Ⅱ)在δ-MnO_2和γ-MnOOH两种矿物上吸附的初始溶质浓度效应  

Initial adsorbate concentration effect on adsorption reversible /irreversible systems of Zn (Ⅱ) at δ-MnO_2 and γ-MnOOH Water Interface

作　　者：李晋[1] 陈灏[1] 潘纲[1] 高美媛[1] 

机构地区：[1]中国科学院生态环境研究中心环境水质学国家重点实验室,北京100085

出　　处：《环境科学学报》2006年第10期1606-1610,共5页Acta Scientiae Circumstantiae

基　　金：国家自然科学基金(No.20073060);中科院优秀"百人计划"资助项目~~

摘　　要：研究了在Zn(Ⅱ)总量一定的情况下,不同的初始溶质浓度和吸附动力学过程对吸附等温线及吸附不可逆性的影响.将总量一定的吸附质Zn(Ⅱ),分批次(1次,3次,15次)加入到2种不同的吸附剂体系(δ-MnO2和γ-MnOOH)中,得到吸附等温线.实验结果表明,对于Zn(Ⅱ)-δ-MnO2吸附可逆体系,吸附-解吸等温线及可逆性随着Zn(Ⅱ)加入批次的增加未见明显变化;而对于Zn(Ⅱ)-γ-MnOOH吸附不可逆体系,吸附等温线随着Zn(Ⅱ)加入批次的增加显著升高,吸附量变大,吸附不可逆性降低.这主要是由于在两种矿物上的微观吸附状态不同所导致的,而这种差异是受吸附动力学过程影响的,这是传统吸附热力学所不能解释的,但是符合亚稳平衡态吸附(MEA)理论的预测.The effect of initial adsorbate concentrations and adsorption kinetic processes on adsorption isotherms and adsorption irreversibility was studied, by introducing a same total amount of Zn （ Ⅱ ） into 2 different adsorption solutions （δ-MnO2 and γ-MnOOH） in various batches （ 1,3, and 15 batches）. No significant changes in adsorption-desorption isotherms and adsorption reversibility with increasing adding batches of Zn （Ⅱ） was observed in the reversible Zn （Ⅱ ）-δ-MnO2 adsorption system. Under the same condition, however, adsorption density increased substantially with the increasing number of adding batches, while irreversibility decreased obviously in the irreversible Zn （ Ⅱ ） -γ-MnOOH adsorption system. These phenomena were possibly caused by different microscopic structures of hydrated Zn （ Ⅱ ） on the 2 minerals, which would be influenced by adsorption kinetic proeesses, well in line with the Mctastable Equilibrium Adsorption （MEA） theory.

关 键 词：Zn(Ⅱ) Δ-MNO2 Γ-MNOOH 吸附不可逆性 初始溶质浓度效应 

分 类 号：X131.2[环境科学与工程—环境科学]