壳聚糖基磁性树脂对Au^3＋和Ag^＋的吸附 Ⅱ吸附热力学和穿透曲线研究  

ADSORPTION PROPERTIES OF CHITOSAN-BASED MAGNETIC RESINS TOWARD Au^(3+) AND Ag^+ Ⅱ. STUDY ON THERMODYNAMICS AND BREAKTHROUGH CURVES

作　　者：周利民[1,2] 王一平[2] 黄群武[2] 刘峙嵘[1] 

机构地区：[1]东华理工大学核资源与环境教育部重点实验室,江西抚州344000 [2]天津大学化工学院,天津300072

出　　处：《离子交换与吸附》2008年第6期518-525,共8页Ion Exchange and Adsorption

基　　金：江西省教育厅科技项目(No.GJJ08302);东华理工大学核资源与环境中心开放测试基金(No.070710)

摘　　要：利用硫脲改性的壳聚糖基磁性微球(TMCS)吸附Au3+和Ag+。利用静态吸附法考察了不同温度下Au3+和Ag+的吸附等温线;利用柱吸附法考察了进液流率、床层高度对穿透曲线的影响。结果表明,随温度升高,Au3+和Ag+的吸附容量下降;焓变(△H°)为负,表明吸附过程放热;Gibbs自由能(△G°)为负,表明吸附反应能自发进行。随进液流率增加或床层高度下降,穿透曲线前移;由BDST模型(Beddepth service time model)得出的临界床层高度分别为:Au3+2.34cm;Ag+3.41cm。TMCS有良好的重复使用性。The magnetic chitosan-based resins modified with thiourea （TMCS） were studied for Au^3＋ and Ag^＋ adsorption from the aqueous solution. The adsorption isotherms of Au^3＋ and Ag^＋ at different temperatures were investigated using batch methods. The breakthrough curves of the uptake of Au^3＋ and Ag^＋ by TMCS at various flow rates and bed height of the adsorbents were investigated using column adsorption. The results showed that the adsorption capacity of both Au^3＋ and Ag^＋ decreased with temperature increasing. The negative values of enthalpy （△H°） indicates that the adsorption process is exothermic whereas the negatives values of Gibbs free energy （△G°） suggests that the adsorption reaction is spontaneous. The breakthrough time became earlier with the flow rate increasing or the bed height decreasing. The critical bed height for Au^3＋ and Ag^＋ were calculated by BDST （bed depth service time model） as 2.34cm and 3.41cm, respectively. TMCS also showed excellent reusability.

关 键 词：硫脲 壳聚糖 磁性吸附 金属离子 

分 类 号：O647.3[理学—物理化学]