Please use this identifier to cite or link to this item:
|Title:||Carrageenan-grafted magnetite nanoparticles as recyclable sorbents for dye removal|
|Author:||Daniel-da-Silva, Ana L.|
Salgueiro, Ana M.
Silva, Nuno J. O.
|Abstract:||The efforts dedicated to improving water decontamination procedures have prompted the interest in the development of efficient, inexpensive, and reusable sorbents for the uptake of dye pollutants. In this work, novel sorbents consisting of carrageenan polysaccharides grafted to magnetic iron oxide nanoparticles were prepared kappa- and iota-carrageenan were first chemically modified by carboxymethylation and then covalently attached via amide bond to the surface of aminated silica-coated magnetite nanoparticles, both steps monitored using infrared spectroscopy (FTIR) analysis. The kinetics and the equilibrium behavior of the cationic dye methylene blue (MB) adsorption onto the carrageenan sorbents were investigated. iota-carrageenan sorbents displayed higher MB adsorption capacity that was ascribed to high content of sulfonate groups. Overall, the pseudo-second order equation provided a good description of the adsorption kinetics. The iota-carrageenan sorbents followed an unusual Z-type equilibrium adsorption isotherm whereas the isotherm of iota-carrageenan sorbents, although displaying a conventional shape, could not be successfully predicted by isotherm models commonly used. Noteworthy, both sorbents were long-term stable and could easily be recycled by simply rinsing with KCl aqueous solution. The removal efficiency of kappa-carrageenan sorbents was 92 % in the first adsorption cycle and kept high (>80 %) even after six consecutive adsorption/desorption cycles.|
|Appears in Collections:||CICECO - Artigos|
Files in This Item:
|Carrageenan-grafted magnetite nanoparticles as recyclable sorbents for dye removal_10.1007s11051-015-3108-0.pdf||1.48 MB||Adobe PDF|
Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.