Portal de Periódicos da CAPES

Artigo Acesso aberto Produção Nacional Revisado por pares

BIBTEX RIS

Adsorção de íons fosfato em óxido de nióbio hidratado

2009; Brazilian Chemical Society; Volume: 32; Issue: 5 Linguagem: Inglês

10.1590/s0100-40422009000500023

1678-7064

Liana Álvares Rodrigues, M. Silva,

Iron oxide chemistry and applications

ADSORPTION OF PHOSPHATE IONS ON HYDROUS NIOBIUM OXIDE.The adsorption kinetics of phosphate on Nb 2 O 5 .nH 2 O was investigated at initial phosphate concentrations 0.25, 0.50 and 1.00 mg.L -1 .The kinetic process was described by a pseudo-secondorder rate model very well.The adsorption thermodynamics was carried out at 298, 308, 318, 328 and 338 K.The positive values of both ∆H and ∆S suggest an endothermic reaction and increase in randomness at the solid-liquid interface during the adsorption.∆G values obtained were negative indicating a spontaneous adsorption process.The Langmuir model described the data better than the Freundlich isotherm model.The effective desorption could be achieved using water at pH 12.