利用CDM-PSS-DGT装置累积测量水中的Ni^(2+)和Co^(2+)  

THE MEASUREMENT OF CDM-PSS-DGT DEVICE FOR Ni^(2+)AND Co^(2+)IN WATER

作　　者：范洪涛[1] 刘畅[1] 朱晓琼[1] 陈宏[1] 仝桂锋[1] 孙挺[1] 

机构地区：[1]东北大学化学系,沈阳110004

出　　处：《环境化学》2009年第1期132-135,共4页Environmental Chemistry

摘　　要：研究了CDM-PSS-DGT装置对Ni^(2+)和Co^(2+)的累积和测量.测定了Ni^(2+)和Co^(2+)与聚乙烯苯磺酸(PSS)的条件配位稳定常数以及Ni^(2+)和Co^(2+)在扩散层中的扩散系数.考察了酸度、离子强度以及碱金属和碱土金属对CDM-PSS-DGT装置累积水中Ni^(2+)和Co^(2+)的影响.在pH 4-9范围内,酸度对Ni^(2+)和Co^(2+)的累积容量影响不大;离子强度对Ni^(2+)和Co^(2+)的累积容量有较强的影响,随着离子强度的不断增大,CDM-PSS- DGT装置对Ni^(2+)和Co^(2+)的累积容量逐渐下降;碱金属、碱土金属与Ni^(2+)和Co^(2+)共存时,CDM-PSS-DGT装置对Ni^(2+)和Co^(2+)优先累积.经测定Ni^(2+)和Co^(2+)与结合相PSS的条件配位稳定常数(lg K)分别为8.04和8.07.配制水中CDM-PSS-DGT装置能准确地对Ni^(2+)和Co^(2+)进行测量,Ni^(2+)和Co^(2+)的测量回收率分别为:93.84%和91.82%,RSD%分别为:3.53%和4.89%.In situ accumulation of Ni^2＋ and Co^2＋ was studied with the diffusive gradients in thin-films （DGT） technique. The effect of pH, ionic strength and the alkali, alkaline earth metals on the binding capacity of CDM-PSS-DGT device were investigated. The CDM-PSS-DGT device had a substantial binding capacity at pH 4--9. The binding capacity of CDM-PSS-DGT device decreased with the enhancement of ionic strength in bulk solution. It showed that the noted interference of the alkali, alkaline earth metals for the accumulation of Ni^2＋ and Co^2＋ was not found in the bulk solution. The conditional complex constants of PSS with Ni^2＋ and Co^2＋ have been measured （ lg K （ Ni^2＋ ） = 8.04, lg K （ Co^2＋ ） = 8.07） . Validation was undertaken for Ni^2＋ and Co^2＋ in synthetic solution （ Recovery = 93.84% RSD=3.53% for Ni^2＋ ; Recovery = 91.82 %, RSD4. 89% for Co^2＋ ） . The CDM-PSS-DGT device shows good prospect for the in-situ accumulation of Ni^2＋ and Co^2＋ in natural waters.

关 键 词：薄膜扩散梯度 累积 测量 镍 钴. 

分 类 号：X832[环境科学与工程—环境工程]