闽江水体镉的络合容量和配合物易变性常数  

COMPLEXING CAPACITY AND SOLUBLE COMPLEX LABILITY OF CADMIUM IN THE MINJIANG RIVER

作　　者：杨利民[1] 倪志鑫[1] 李晓波[1] 林竹光[1] 王秋泉[1] 

机构地区：[1]厦门大学化学化工学院,教育部现代分析科学重点实验室,厦门361005

出　　处：《环境化学》2008年第6期795-799,共5页Environmental Chemistry

基　　金：国家自然科学基金(20175019;20775062)资助项目

摘　　要：以双硫腙为萃取剂建立了天然水中镉的络合容量(CdCC)及相应配合物易变性常数(kobsd)的测定方法.用乙二胺四乙酸、N-(2-羟乙基)乙二胺-N,N,′N′-三乙酸、氨三乙酸以及腐殖酸模拟天然水中的有机配体,验证了方法的可行性.将此方法应用于闽江流域不同河段水样的分析,测得CdCC为7.23—7.85μmol·l-1,kobsd在2.5×10-2—2.8×10-2s-1之间,与腐殖酸模型溶液相近.CdCC与水体中可溶性有机碳以及硫的含量有一定的相关性,人类活动和生态环境影响天然水体中有机物的种类和含量及相应的CdCC.Using dithizone as a competing ligand, a dynamic extraction method for determining cadmium complexing capacity （CdCC） and cadmium complex lability （ kobsd） of natural waters was established. The feasibility of the method was validated using the mimic water samples containing some typical model chelating ligands such as ethylenediaminetraacetic acid, N- （2-hydroxyethyl） ethylene-diamine-N, N; N＇-triacetic acid, nitrilotriacetic acid and humic acid. The method was applied to determine CdCC and kobsd of the real water samples collected from different sites of the Minjiang River in southeastern China. The CdCC and kobsd are from 7.23 to 7. 85μmol ·l^-1and from 2. 5 × 10^-2 to 2.8 × 10^ -2 s^-1, respectively, which are similar to those of the humic acid mimic water sample. Results also indicated the CdCC is correlated to the dissolved organic carbon and sulfur contents of the waters. Furthermore, the influences of the anthropogenic activities and natural geography around the sampling sites on the CdCC were discussed.

关 键 词：镉 络合容量 易变性常数 天然水体 

分 类 号：X132[环境科学与工程—环境科学]