改性腐植酸对稀土离子La^(3+),Ce^(3+)吸附性能研究  

Adsorption Properties of Modified Humic Acid to Rare Earth La^(3+),Ce^(3+)

作　　者：杨睿琳 刘亚淳[1] 朱科[1] 黄皓[1] 廖洋[1] 赵仕林[1] 

机构地区：[1]四川师范大学化学与材料科学学院,四川成都610068

出　　处：《中国稀土学报》2016年第5期585-591,共7页Journal of the Chinese Society of Rare Earths

基　　金：国家自然科学基金项目(51173122;21406147);成都市科技局项目(2014-HM01-00205-SF;2014-HM01-00204-SF);大学生科创项目(201510636009);四川师范大学研究生优秀论文培育基金项目(20160435)资助

摘　　要：以腐植酸(HA)为原料,经两步酯化制备了改性腐植酸(HAE)吸附材料,用IR,SEM对HAE进行了表征,并考察了pH值、温度、离子浓度和时间等因素对其吸附行为的影响。实验结果表明:HAE对稀土离子的吸附在30 min左右即可达到平衡,pH值和离子浓度对La^(3+)和Ce^(3+)吸附量有较大影响,但温度对Ce^(3+)吸附量的影响较小。La^(3+)和Ce^(3+)在pH=5.5,T=35℃条件下的饱和吸附容量分别为124.75和583.82mg·g-1,HAE材料对Ce^(3+)的吸附量更大。HAE对La^(3+)和Ce^(3+)吸附过程都适于Freundlich模型,符合拟二级速率方程,重复使用4次,其吸附量变化不大。在模拟稀土废水中,经HAE材料吸附后稀土离子的浓度小于30 mg·L^(-1),达到国家稀土废水排放标准,该材料可用于处理低浓度的稀土废水。The humic acid （HA） was used as raw materials to prepare absorbent （HAE） by two-step esterification reaction. The as-prepared absorbent （HAE） was characterized by Fourier transform infrared spectrometer and scanning electron microscopy. The properties of this adsorbent were systematically investigated under different conditions, such as pH, concentrations, temperature and time, etc. The results indicated that the adsorption equilibrium was reached equilibrium after 30 min. The pH and temperature showed significant effect on adsorption capacity of HAE to La3^＋ , but there was a little influence of temperature on adsorption capacity of Ce3^＋. It indicated that the maximum adsorption capacities of HAE to La3^＋ and Ce3^＋ were 124.75 and 583.82 rag.g-1 （pH = 5.5; T = 35 ℃ ）. Furthermore, It was found that the adsorption kinetics was well described by the adsorption isotherms followed Freundlich （La3^＋, Ce3^＋） adsorption model and the pseudo-second order kinetic model. Repeated four times, adsorption capacity of HAE remained. In simulation rare earth waste water, rare earth ions concentration was less than 30 mg·L^-1 after adsorption reaction, which means the national rare-earth wastewater discharge standard. The material could be used to dispose low concentration of rare earth wastewater.

关 键 词：改性腐植酸 LA^3+ CE^3+ 吸附 

分 类 号：X703[环境科学与工程—环境工程]