摘要
解决离子吸附型稀土矿低浓度浸出液和淋滤水中稀土的截留和回收难题十分必要。以稀土镧离子(La(Ⅲ))为代表,采用包埋羧甲基壳聚糖的二氧化硅微球复合吸附剂(SiO_2/CMCH)从低浓度模拟稀土料液中回收La(Ⅲ),并系统研究了溶液pH、La(Ⅲ)浓度、吸附时间、NaNO_3浓度等对La(Ⅲ)吸附量的影响。结果表明,La(Ⅲ)吸附遵循Langmuir等温吸附模型和准二级动力学模型。在308 K的HCl体系中,SiO_2/CMCH对La(Ⅲ)的饱和吸附容量为23.26 mg/g干吸附剂或190.66 mg/g CMCH。吸附为阳离子交换机理,-NH2具有显著的协同配位效应。稀盐酸可以实现对负载在SiO_2/CMCH中La(Ⅲ)的完全解吸,且吸附剂可循环再生。
It is necessary to solve the problem of interception and recovery of rare earth in low - concentration leaching water. Taking lanthanum ions as the object, this work reported the recovery of lanthanum(Ⅲ) ions from aqueous solution by earboxymethyl chitosan adsorbents entrapped by silica (SiOJCMCH). The effects of equilibrium pH, contact time, initial concentrations of La(Ⅲ) and NaNO3 on the adsorption were investigated. It was found that adsorption kinetics and i- sotherm could be described by the pseudo -second -order model and Langmuir equation. The La(Ⅲ) adsorption amounts calculated by Langmuir equation were 23.26 mg/g dry adsorbent or 190.66 mg/g CMCH at 308 K. The adsorption mechanism was cation exchange, and - NH2 had significant synergistic effect. The dilute hydrochloric acid could completely desorb La (Ⅲ) in SiO2/ CMCH, and the adsorbent was recycled.
出处
《矿产保护与利用》
北大核心
2017年第3期68-74,共7页
Conservation and Utilization of Mineral Resources
基金
国家自然科学基金项目(51504073
51404081)
贵州省科学技术基金(黔科合LH[2014]7373)
贵州省教育厅自然科学基金项目(黔教科合KY[2015]433)
贵州理工学院高层次人才基金项目(XJG20141104)
关键词
羧甲基壳聚糖
二氧化硅微球
吸附
稀土
carboxymethyl chitosan
silica microspheres
adsorption
rare earths