7-amino-4-azaheptyl grafted onto a silica gel as a sorbent for the on-line preconcentration and determination of iron(III) in water samples

• Autor(a) principal: Moraes, Sandra Valéria Mendes de
• Data de Publicação: 2005
• Outros Autores: Tissot, Mateus Marques, Milcharek, Caroline D., Brasil, Jorge de Lima, Costa, Tania Maria Haas, Gallas, Marcia Russman, Benvenutti, Edilson Valmir, Lima, Éder Cláudio
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Repositório Institucional da UFRGS
• Texto Completo: http://hdl.handle.net/10183/206298
• topic: Gel de sílica : Síntese

A new sorbent was synthesized by anchoring 7-amino-4-azaheptyltrimetoxisilane, freshly prepared, to silica gel, producing 7-amino-4-azaheptyl anchored silica gel (AAHSG). This material was characterized by infrared spectroscopy (IR), elemental analysis (CHN), and nitrogen adsorption-desorption isotherms. Isotherms of the adsorption of Fe3+, Fe2+ and Cu2+ on AAHSG were recorded, which indicated that Fe3+ presents a higher affinity by the sorbent. Therefore, AAHSG was successfully employed as a sorbent in a simple flow system for the preconcentration of Fe3+ in natural water samples, such as, river water, lagoonwater, springwater, stream water, well water and two water reference materials (NIST-SRM 1640, NIST-SRM 1643d). The obtained preconcentration factor was 82.2, and the detection limit achieved was 5.9 ng ml-1. The recovery of spiked water samples ranged from 95.0 - 103.1%.