Adsorption ability of oxidized multiwalled carbon nanotubes towards aqueous Ce(III) and Sm(III)

• Published in: The Korean journal of chemical engineering Vol. 30; no. 2; pp. 448 - 455
• Main Authors: Behdani, Fattaneh Naderi, Rafsanjani, Alireza Talebizadeh, Torab-Mostaedi, Meisam, Mohammadpour, Seyed Mohammad Amin Koochaki
• Format: Journal Article
• Language: English
• Published: Boston Springer US 01-02-2013; 한국화학공학회
• Subjects: Biotechnology; Catalysis; Chemistry; Chemistry and Materials Science; Industrial Chemistry/Chemical Engineering; Materials Science; Separation Technology; Thermodynamics; 화학공학; Adsorption; Cerium; Isotherm; Desorption; Samarium; Kinetics; Multiwalled Carbon Nanotubes (MWCNTs)
• ISSN: 0256-1115; 1975-7220
• DOI: 10.1007/s11814-012-0126-9

The aim of the present work was to investigate the adsorption of Ce(III) and Sm(III) onto multiwalled carbon nanotubes (MWCNTs) oxidized with concentrate nitric acid. The effects of solution pH, adsorbent dosage, and contact time were studied by batch technique. Langmuir, Freundlich and D-R isotherms were used to describe the adsorption behavior of Ce(III) and Sm(III) by oxidized MWCNTs, and the experimental results fitted Freundlich model well. The maximum uptake capacities (q
m
) calculated by applying the Langmuir equation for samarium and cerium ions were found to be 89.28 and 92.59 (mg/g), respectively. A comparison of the kinetic models and the overall experimental data was best fitted by the pseudo second-order kinetic model. The calculated thermodynamic parameters (ΔG
o
, ΔH
o
, and ΔS
o
) showed that the adsorption for Ce(III) and Sm(III) is feasible, spontaneous and exothermic at 30–60 °C. Moreover, more than 70% of Ce(III) and Sm(III) adsorbed onto Oxidized MWCNTs could be desorbed with HNO
3
.