CAJ | 학술논문

采用膨润土经提纯、钠化及负载铁等过程制备铁负载膨润土,通过静态吸附实验研究了pH、离子强度、吸附剂投加量、U( VI)初始浓度、阳离子Ca2+、Mg2+以及阴离子CO32-、HCO3-等对铁负载膨润土吸附模拟废水中U(VI)的影响,进行了吸附过程动力学、热力学分析,并利用傅里叶红外光谱( FT-IR)、扫描电镜( SEM)探讨了相关吸附机理.试验结果表明,pH值和离子强度是影响吸附效果的重要因素,当溶液pH为6,离子强度为0.01 mol/L NaNO3,U(VI)初始浓度为19.08 mg/L,铁负载膨润土投加量为0.2 g/L,24 h吸附量达到88.06 mg/g.当pH<6时,Ca2+、Mg2+、CO32-、HCO3-的存在分别降低了铁负载膨润土对U( VI)的吸附效果,而pH>7时影响作用不大.准二级动力学和Langmuir等温吸附模型对铁负载膨润土吸附U( VI)的拟合效果较好,SEM和FT-IR分析结果表明铁负载膨润土主要通过羟基络合及离子交换作用结合U( VI)进入其层间及表面.
채용팽윤토경제순、납화급부재철등과정제비철부재팽윤토,통과정태흡부실험연구료pH、리자강도、흡부제투가량、U( VI)초시농도、양리자Ca2+、Mg2+이급음리자CO32-、HCO3-등대철부재팽윤토흡부모의폐수중U(VI)적영향,진행료흡부과정동역학、열역학분석,병이용부리협홍외광보( FT-IR)、소묘전경( SEM)탐토료상관흡부궤리.시험결과표명,pH치화리자강도시영향흡부효과적중요인소,당용액pH위6,리자강도위0.01 mol/L NaNO3,U(VI)초시농도위19.08 mg/L,철부재팽윤토투가량위0.2 g/L,24 h흡부량체도88.06 mg/g.당pH<6시,Ca2+、Mg2+、CO32-、HCO3-적존재분별강저료철부재팽윤토대U( VI)적흡부효과,이pH>7시영향작용불대.준이급동역학화Langmuir등온흡부모형대철부재팽윤토흡부U( VI)적의합효과교호,SEM화FT-IR분석결과표명철부재팽윤토주요통과간기락합급리자교환작용결합U( VI)진입기층간급표면.
The Fe-immobilized bentonite was prepared by purification,sodium and load of iron compounds. The adsorption properties of U ( VI ) onto Fe-immobilized bentonite was investigated at various conditions of initial solution pH, ionic strength, adsorbent dosage U( VI) concentration,as well as adding Ca2+, Mg2+, CO3 2-, HCO3- by batch technique. Conducted adsorption kinetics, thermodynamics analysis, Fe-immobilized before and after adsorption were characterized by Scanning Electrion Microscope( SEM) and Fourier Trans-form Infrared Spectra( FT-IR) . Results indicated that the adsorption capacity were strongly affected by the solution pH and ion strength,the adsorption capacity reached 88. 06 mg/g after 24 h when U(VI) concentration was 19. 08 mg/L and Fe-immobilized bentonite dos-age was 0. 2 g/L. The common ions of Ca2+,Mg2+,CO32-,HCO3-in natural water reduced the adsorption of U ( VI ) by Fe-immobilized bentonite as pH <6 , but had no significant effect as pH>7 . The adsorption kinetics process was fitted well with the second-order ki-netic equation, simultaneously the Langmuir equations could describe the adsorption iso-therm of U( VI) well. Based on SEM and FT-IR instruments,we found U( VI) main entry bentonite layer and surface by hydroxy complex and ion exchange.