摘要
淋洗剂EDTA二钠和柠檬酸三钠与镉形成的络合物及镉本身在黏土上的吸附行为研究表明:上述两种淋洗剂能有效提取表层土中的Cd,形成的络合物在迁移过程中又能较好地被黏土层吸附。黏土对Cd2+、Cd-EDTA和Cd-柠檬酸的吸附容量顺序为:Cd-柠檬酸>Cd2+>Cd-EDTA;3种形态的吸附过程均以离子交换吸附为主,并在15 min内完成。黏土对Cd2+和Cd-柠檬酸的吸附容量随溶液初始pH的升高而增大,对Cd-EDTA的吸附容量随pH升高略有降低。
The adsorption behaviors of cadmium and its complexes with two kinds of eluents including EDTA disodium and trisodium citrate on clay were studied.The results showed that the two kinds of eluents had strong chelating ability for cadmium in topsoil,and the complexes were strongly adsorbed by clay in their transport process.The sequence of adsorption capacities of clay was：Cd—citrate Cd2＋Cd—EDTA,and the main sorption mechanism of the three forms were ion-exchange absorption and could be obtained in 15 min.The adsorption quantity of clay increased to Cd2＋ and Cd—citrate and slightly decreased to Cd—EDTA,along with the increasing of initial pH value in solution.
出处
《世界地质》
CAS
CSCD
2010年第4期663-667,共5页
World Geology
基金
国家科技重大专项(2008ZX07207-007-04)
关键词
镉
镉络合物
黏土
吸附
Cd
cadmium complexes
clay
adsorption
