水化学条件对海泡石吸附重金属镍(Ni^(2+))离子的影响及其机制研究  

STUDY ON THE EFFECTS AND MECHANISM OF WATER CHEMISTRY CONDITIONS TO ADSORPTION OF NI^(2+) ON SEPIOLITE

作　　者：罗伟锋[1] 叶海林[1] 富潇彬[1] 薛笋静[1] 叶细首[1] 柴少龙[1] 周虹[1] 楼华敏[1] 

机构地区：[1]煤炭科学研究总院杭州环保研究院,浙江杭州311201

出　　处：《能源环境保护》2012年第4期18-22,共5页Energy Environmental Protection

摘　　要：本论文用静态实验法研究了重金属镍(Ni2+)离子在海泡石上的吸附行为和机理,考察了平衡时间、pH值、离子强度、腐殖酸、背景电解质阴、阳离子等水化学条件对吸附作用的影响。结果发现:Ni(II)在海泡石上的吸附在很短的时间里就可以达到平衡。Ni(II)在海泡石上的吸附受体系pH值和离子强度影响很大,在酸性条件下,主要吸附机理是外层络合和离子交换,而在碱性条件下,主要的吸附机理是内层络合。背景电解质阴、阳离子对Ni(II)在海泡石上的吸附有一定的促进或抑制作用。在低pH值下,腐殖酸在海泡石上吸附后形成了新的表面络合物而增强Ni(II)的吸附,而在高pH值的条件下,腐殖酸存在于吸附体系时,Ni(II)的吸附量明显小于Ni(II)/海泡石吸附体系。本为的研究结果为环境中重金属离子和放射性核素的危害评估和有效治理提供了很好的参考。The adsorption behavior and mechanism of Ni^2＋ on sepiolite were studied by static experiment method in this work, and the effects of water chemistry conditions including balance time, pH, ionic strength, humic acid, anions and cations of background electrolyte on adsorption were investigated. The results showed that the adsorption of Ni^2＋ on sepiolite came to the balance in short time, and this adsorption was strongly affected by pH and ionic strength of reaction medium according to the following patterns： Ni^2＋ions were adsorbed on sepiolite by outer complexation and ion exchange in acidic mediums; while, under alkaline conditions, the adsorption mechanism was changed into inner complexation. The anions and cations of background electrolyte showed positive or negative effects on the adsorption of Ni^2＋ on sepiolite. Under the condition of low pH, the adsorption of humic acid on sepiolite could produce the surface complex, which would enhance the adsorption of Ni^2＋ on sepiolite; in the medium at high pH, the humic acid was adsorbed in the system, and the adsorption amount of Ni^2＋ was much lower than the system of Ni^2＋sepiolite. This result will provide beneficial reference for hazard assessment and effective management of heavy metal ions and radionuclide in the environment.

关 键 词：海泡石 吸附 腐殖酸 镍离子 

分 类 号：X703[环境科学与工程—环境工程]