(1. 北京矿冶研究总院，北京 100160；
2. 东北大学 冶金学院，沈阳 110006；
3. 中国科学院 过程工程研究所 湿法冶金清洁生产技术国家工程实验室，北京 100190；
4. 北京科技大学 冶金与生态制造工程学院，北京 100083)
摘 要: 本文以成型壳聚糖为吸附剂进行溶液中Ni-Co的分离，通过Ni2+和Co2+与壳聚糖上氨基的络合能力差异达到Ni2+、Co2+分离的目的。结果表明：利用NaOH与壳聚糖醋酸溶液可制备出粒度约为60 μm的层状成型壳聚糖；成型壳聚糖对Ni2+、Co2+的吸附符合拟二级动力学方程和Freundlich方程；经吸附焓变计算发现成型壳聚糖对Ni2+的吸附为吸热反应，而对Co2+的吸附为放热反应；吸附机理表明，壳聚糖上的氨基和羟基与Ni2+、Co2+发生结合反应。以萃取分离后得到的高Co2+低Ni2+溶液为原料，成型壳聚糖吸附后溶液中Ni2+含量由73×10-6降低至30×10-6，实现杂质的深度脱除。
关键词: 镍；钴；吸附；选择性分离；壳聚糖；改性
（1. Beijing General Research Institute of Mining & Metallurgy, Beijing 100160, China;
2. School of Metallurgy, Northeastern University, Shenyang 110006, China;
3. National Engineering Laboratory for Hydrometallurgical Cleaner Production Technology, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China;
4. School of Metallurgical and Ecological Engineering, University of Science and Technology Beijing, Beijing 100083, China）
Abstract:Ni and Co are difficult from separation due to their similar physicochemical properties. Based on the difference in complexation ability between ammonia and Ni/Co, selective separation of Ni2+ and Co2+ was conducted by using modified chitosan as adsorbent with amino group. The results show that the modified chitosan with the size of 60 μm can be prepared by mixing chitosan-acetic acid solution with NaOH. The adsorption behavior of Ni2+ and Co2+ onto modified chitosan, including adsorption isotherm and kinetics, is fitted well by Freundlich model and pseudo-second- order model, respectively. Adsorption enthalpy results indicate that the Ni2+ uptake onto modified chitosan is endothermic while the Co2+ uptake is exothermic. The adsorption mechanism shows that the Ni2+ and Co2+ are chelated with amino and hydroxyl groups of modified chitosan. In the specific application, Ni2+ content of high concentrated Co2+ solutions decreases from 73×10-6 to 30×10-6, realizing the selective separation of Ni.
Key words: nickel and cobalt; adsorption; selective separation; chitosan; modification
