%0 Journal Article
%T Adsorption and desorption behavior of Tl(I) in river sediments<br>铊在河流沉积物上的吸附解吸行为研究
%A WANG Xin
%A YANG Xiaofang
%A WANG Dongsheng
%A XIA Hua
%A <br>王新
%A 杨晓芳
%A 王东升
%A 夏华
%J 环境科学学报
%D 2013
%I 
%X The water environment has a direct effect on the adsorption and desorption behavior of thallium (Tl) in sediments and further influences its transportation and transformation. In this study, the adsorption behavior of Tl(I) and the effect of pH on the adsorption in sediments taken from Liangshui River of Beijing (L8) and the nearby lotus pond (L6) was investigated. In addition, background electrolyte and sediment leaching solutions were used as the desorption system to examine the desorption characteristics of adsorbed Tl(I) from the sediments. Results indicated that the rates of absorption of Tl(I) onto both sediments were relatively fast, with adsorption capacities reaching 90% of the maximum (L6) and over 80% of the maximum (L8) in the initial five minutes, and the adsorption equilibrium was reached after 12 hours of reaction. With the increased initial concentration of Tl(I), the adsorption capacities of Tl(I) in sediments of L6 and L8 increased, and the adsorption capacity of Tl(I) on L6 was remarkably higher than that of on L8. Adsorption isotherms of Tl(I) on the two sediments fit well with both the Freundlich and Langmuir equation. On the analysis of mechanism of adsorption and desorption, the Langmuir equation could better illustrate its chemical and physical properties than that of Freundlich equation. pH had a great effect on the adsorption of Tl in sediments. The adsorption capacity increased gradually with the increase of the pH. The sediment leaching solution was characterized by high pressure size exclusion chromatography (HPSEC) and fluorescence excitation-emission matrix (EEM) spectrometry. The results showed that the main components in the leaching solution were proteinoid and humic substance with fluorescence intensity between 1100 and 1550. When the sediment leaching solution was used as desorption system, the desorption amount of Tl(I) increased about 2.232 mg·kg-1 (L6) and 1.494 mg·kg-1 (L8) (C0=0.33 mg·L-1). Desorption of Tl(I) in the sediment leaching solution was easier compared to NaNO3 background solution, leading to a release of Tl(I) back into the water environment.
%K thallium
%K sediments
%K adsorption and desorption<br>铊
%K 沉积物
%K 吸附解吸
%U http://www.alljournals.cn/get_abstract_url.aspx?pcid=3ff3aba7486768130c3ff830376f43b398e0c97f0ff2dd53&cid=a7ca601309f5fed03c078bce383971dc&jid=03a55e61a8750acac6af81ef9e2ac838&aid=9c65539b20e123fc6cfafdefa342a31e&yid=ff7aa908d58e97fa&vid=27746bceee58e9dc&iid=0b39a22176ce99fb&sid=a726e84831fe609b&eid=ba305a52e2ee9350&journal_id=0253-2468&journal_name=环境科学学报&referenced_num=0&reference_num=35