Th(IV) Adsorption onto Oxidized Multi-Walled Carbon Nanotubes in the Presence of Hydroxylated Fullerene and Carboxylated Fullerene

Materials

Jing Wang²  Peng Liu²  Zhan Li¹  Wei Qi²  Yan Lu³ 

[1] Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000, China; E-Mail:;Radiochemistry Laboratory, School of Nuclear Science and Technology, Lanzhou University, Lanzhou 730000, China; E-Mails:;China National Nuclear Corporation Lanzhou Uranium Enrichment Co., Ltd., Lanzhou 730000, China; E-Mail:

关键词: influence;    C₆₀(OH)_n;    C₆₀(C(COOH)₂)_n;    Th(IV) adsorption;    oMWCNTs;   

DOI  :  10.3390/ma6094168

来源: mdpi

【 摘 要 】

The adsorption of Th(IV) onto the surface of oxidized multi-walled carbon nanotubes (oMWCNTs) in the absence and presence of hydroxylated fullerene (C₆₀(OH)_n) and carboxylated fullerene (C₆₀(C(COOH)₂)_n) has been investigated. C₆₀(OH)_n, C₆₀(C(COOH)₂)_n and oMWCNTs have been chosen as model phases because of their representative in carbon nano-materials family. Adsorption experiments were performed by batch procedure as a function of contact time, pH, ionic strength, and temperature. The results demonstrated that the adsorption of Th(IV) was rapidly reached equilibrium and the kinetic process could be described by a pseudo-second-order rate model very well. Th(IV) adsorption on oMWCNTs was dependent on pH but independent on ionic strength. Adsorption isotherms were correlated better with the Langmuir model than with the Freundlich model. The thermodynamic parameters calculated from temperature-dependent adsorption isotherms suggested that Th(IV) adsorption on oMWCNTs was spontaneous and endothermic. Compared with the adsorption of Th(IV) on the same oMWCNTs free of C₆₀(OH)_n or C₆₀(C(COOH)₂)_n, the study of a ternary system showed the inhibition effect of C₆₀(OH)_n at high concentration on the adsorption of Th(IV) in a pH range from neutral to slightly alkaline; whereas the promotion effect of C₆₀(C(COOH)₂)_n, even at its low concentration, on Th(IV) adsorption was observed in acid medium.

【 授权许可】

CC BY   
© 2013 by the authors; licensee MDPI, Basel, Switzerland.