Yang Shitong, Li Jiaxing, Shao Dadong, Hu Jun, Wang Xiangke
Key Lab of Novel Thin Film Solar Cells, Institute of Plasma Physics, Chinese Academy of Sciences, P.O. Box 1126, 230031 Hefei, PR China.
J Hazard Mater. 2009 Jul 15;166(1):109-16. doi: 10.1016/j.jhazmat.2008.11.003. Epub 2008 Nov 12.
The adsorption of Ni(II) on oxidized multi-walled carbon nanotubes (MWCNTs) as a function of contact time, pH and foreign ions in the absence and presence of polyacrylic acid (PAA) was studied using batch technique. The results indicated that adsorption of Ni(II) on oxidized MWCNTs increased from zero to approximately 99% at pH 2-9, and then maintained the high level with increasing pH. Kinetic data showed that the adsorption process achieved equilibrium within 2h and experimental data were fitted well by the pseudo-second-order equation. A positive effect of PAA on Ni(II) adsorption was found at pH<8, whereas a negative effect was observed at pH>8. The effect of addition sequences of PAA/Ni(II) on the adsorption of Ni(II) to PAA-MWCNT hybrids were also studied. The results indicated that the adsorption of Ni(II) was influenced by addition sequences obviously. The adsorption of Ni(II) on oxidized MWCNTs may be mainly attributed to surface complexation and ion exchange. Oxidized MWCNTs are suitable material in the solidification and pre-concentration of Ni(II) from aqueous solutions.
采用分批技术研究了在有无聚丙烯酸（PAA）存在的情况下，Ni(II)在氧化多壁碳纳米管（MWCNTs）上的吸附与接触时间、pH值及外来离子的关系。结果表明，在pH为2 - 9时，Ni(II)在氧化MWCNTs上的吸附率从零增加到约99%，然后随着pH值的升高保持在高水平。动力学数据表明，吸附过程在2小时内达到平衡，实验数据与准二级方程拟合良好。在pH < 8时发现PAA对Ni(II)吸附有正向作用，而在pH > 8时观察到负向作用。还研究了PAA/Ni(II)添加顺序对Ni(II)在PAA - MWCNT杂化物上吸附的影响。结果表明，添加顺序对Ni(II)的吸附有明显影响。Ni(II)在氧化MWCNTs上的吸附可能主要归因于表面络合和离子交换。氧化MWCNTs是从水溶液中固化和预富集Ni(II)的合适材料。
