title: Nanoparticles of octakis[3-(3-amino-1,2,4-triazole)propyl]octasilsesquioxane as ligands for Cu(II), Ni(II), Cd(II), Zn(II), and Fe(III) in aqueous solution.
abstract: Nanoparticles of octakis[3-(3-amino-1,2,4-triazole)propyl]octasilsesquioxane (ATZ-SSQ) were tested as ligands for transition-metal ions in aqueous solution with a special attention to sorption isotherms, ligand-metal interaction, and determination of metal ions in natural waters. The adsorption potential of the material ATZ-SSQ was compared with related [3(3-amino-1,2,4-triazole)propyl]silica gel (ATZ-SG). The adsorption was performed using a batchwise process and both organofunctionalized surfaces showed the ability to adsorb the metal ions from aqueous solution. The Langmuir model was used to simulate the sorption isotherms. The results suggest that the sorption of these metals on ATZ-SSQ and ATZ-SG occurs mainly by surface complexation. The equilibrium condition is reached at time lower than 3 min for ATZ-SSQ, while for ATZ-SG is only reached at time of 25 min. The maximum metal ion uptake values for ATZ-SSQ were higher than the corresponding values achieved with the ATZ-SG. In order to obtain more information on the ligand-metal interaction of the complexes on the surface of the ATZ-SSQ nanomaterial, ESR study with various degrees of copper loadings was carried out. The ATZ-SSQ was tested for the determination (in flow using a column technique) of the metal ions present in natural waters.
authors: Departamento de Física e Química, UNESP-Universidade Estadual Paulista, Av. Brasil, 56-Centro, Caixa Postal 31, 15385-000 Ilha Solteira, SP, Brazil. nldias@dffq.feis.unesp.br
authors: Newton Luiz Dias
authors: NL
authors: Filho
authors: Reginaldo Mendonça
authors: RM
authors: Costa
authors: Fabiane
authors: F
authors: Marangoni
authors: Denise Souza
authors: DS
authors: Pereira
mesh_terms: D008024:Ligands; D019216:Metals, Heavy / Q000737:chemistry*; D015394:Molecular Structure; D053758:Nanoparticles / Q000737:chemistry*; D017646:Organosilicon Compounds / Q000138:chemical synthesis / Q000737:chemistry*; D010316:Particle Size; D033362:Powder Diffraction; D012996:Solutions / Q000737:chemistry; D013056:Spectrophotometry, Ultraviolet / Q000379:methods; D013499:Surface Properties; D014867:Water / Q000737:chemistry
chemical_list: D008024:Ligands; D019216:Metals, Heavy; D017646:Organosilicon Compounds; D012996:Solutions; C525616:octakis(3-(3-amino-1,2,4-triazole)propyl)octasilsesquioxane; D014867:Water