Adsorption of Co(II), Ni(II), Cu(II), and Zn(II) on hexagonal templated zirconia obtained thorough a sol-gel process: the effects of nanostructure on adsorption features.
Using zirconium tetrabutoxide, diaminedecane, and diamineoctane as precursors, a templated hexagonal zirconia matrix is synthesized and characterized by X-ray diffractometry and scanning electron microscopy. The adsorption capacity of such a matrix toward Co(II), Ni(II), Cu(II), and Zn(II) from aqueous solutions is studied. The adsorption affinity of the synthesized hexagonal templated zirconia toward the cations is Cu(II)>Zn(II) >>Ni(II)>Co(II). It is also verified that the adsorption of the cations follows a Langmuir and not a Freundlich isotherm. All obtained isotherms are of type I, according to the IUPAC classification. The observed adsorption affinity sequence can be explained by taking into account the velocity constant for the substitution of water molecules into the cation coordination spheres, as well as the Irving-Williams series.
de Farias
Robson F
RF
Departamento de Química, Universidade Federal de Roraima, CP 167, 69301-970 Boa Vista, Roraima, Brazil. robsonfarias@aol.com
do Nascimento
Ana A S
AA
Bezerra
Cícero W B
CW
D000327:Adsorption; D003035:Cobalt / Q000737:chemistry* / Q000493:pharmacokinetics; D003300:Copper / Q000737:chemistry* / Q000493:pharmacokinetics; D005782:Gels / Q000737:chemistry; D049329:Nanostructures; D009532:Nickel / Q000737:chemistry* / Q000493:pharmacokinetics; D044367:Phase Transition; D013499:Surface Properties; D015032:Zinc / Q000737:chemistry* / Q000493:pharmacokinetics; D015040:Zirconium / Q000737:chemistry* / Q000493:pharmacokinetics
D005782:Gels; D003035:Cobalt; D003300:Copper; D009532:Nickel; D015040:Zirconium; D015032:Zinc; C028541:zirconium oxide