Chitosan-silica hybrid nanosorbents for oil removal from water

authors	Soares, SF; Rodrigues, MI; Trindade, T; Daniel-da-Silva, AL
nationality	International
journal	COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
author keywords	Bio-hybrids; Chitosan; Magnetic nanoparticles; Oil-water separation
keywords	MAGNETITE NANOPARTICLES; COLLOIDAL SILICA; IR SPECTROSCOPY; SPILL CLEANUP; RICE HUSKS; CRUDE-OIL; SORBENT; PERFORMANCE; ADSORPTION; MERCURY
abstract	Water pollution caused by oil spills is an environmental problem that raises concerns all over the world. Sorbent materials are of great importance for the removal of the remained oil after skimming operation. Nevertheless owing to reduced size, most sorbents are difficult to collect from water and therefore there is need to develop effective oil sorbents that could be easily separated from aquatic environments. Herein new magnetic nanosorbents composed of magnetite nanoparticles functionalized with chitosan hybrid siliceous shells were successfully prepared using a one-step sol-gel encapsulation method. As a proof of concept, these nanosorbents were tested in the magnetically assisted removal of non-polar organic solvents from water. The characterization of the materials using FTIR spectroscopy, solid-state Si-29 and C-13 NMR spectroscopy and elemental microanalysis confirmed the extensive modification of the particles' shells with chitosan molecules covalently linked to the siliceous domains. These hybrid particles could efficiently adsorb various non-polar organic solvents from water, a behavior that was ascribed to the presence of chitosan macromolecules grafted at the surface of the particles. This is a new type of sorbent with potential application in the removal of oil from water using magnetic separation technologies.
publisher	ELSEVIER SCIENCE BV
issn	0927-7757
year published	2017
volume	532
beginning page	305
ending page	313
digital object identifier (doi)	10.1016/j.colsurfa.2017.04.076
web of science category	Chemistry, Physical
subject category	Chemistry
unique article identifier	WOS:000412065600043