resumo
Pristine, amino monofunctionalized and amino and thiol bifunctionalized phenylene-bridged periodic mesoporous organosilicas (Ph-PMO) were synthetized by a simple methodology without any protection/deprotection steps. The Ph-PMO materials were characterized and their potential as new sorbents for Hg(II) was investigated for low-contamination scenarios. The materials have well-ordered mesostructures as confirmed by powder X-ray diffraction and transmission electron microscopy analyses. C-13 and Si-29 solid-state NMR confirm the amination of the phenylene bridge of the simple Ph-PMO to form the amine-functionalized PMO (NH2-Ph-PMO) and the grafting of the thiol silylated ligand to the free silanols of the NH2-Ph-PMO to obtain the bifunctional (NH2-Ph-PMO-SH). For the initial conditions tested, the bifunctional material showed excellent Hg(II) removal efficiency (98%) and Hg(II) uptake time (30 min). The sorption kinetics were also investigated by three of the most studied kinetic models, and the pseudo-second-order kinetic model was the one that better described the kinetic sorption process of Hg(II) ions onto all PMO. (C) 2017 Elsevier B.V. All rights reserved.
palavras-chave
HEAVY-METAL IONS; PHENYLENE-SILICA; ORGANIC GROUPS; AQUEOUS-MEDIA; LARGE-PORE; ADSORPTION; ADSORBENT; HG(II); REMEDIATION; FRAMEWORKS
categoria
Engineering
autores
Lourenco, MAO; Figueira, P; Pereira, E; Gomes, JRB; Lopes, CB; Ferreira, P
nossos autores
Cláudia Batista Lopes
Investigador Auxiliar
José R. B. Gomes
Investigador Principal
Mirtha A. O. Lourenço
Investigador
Paula Figueira
Bolseiro de investigação
Paula Celeste da Silva Ferreira
Investigador CoordenadorGrupos
G1 - Materiais Porosos e Nanossistemas
G2 - Materiais Fotónicos, Eletrónicos e Magnéticos
G6 - Materiais Virtuais e Inteligência Artificial
Projectos
CICECO - Aveiro Institute of Materials (UID/CTM/50011/2013)
RMNE-UA-National Network of Electron Microscopy (REDE/1509/RME/2005 )
agradecimentos
This work was developed in the scope of the projects CICECO-Aveiro Institute of Materials (POCI-01-0145-FEDER-007679|Ref. FCT UID/CTM/50011/2013); CESAM (Ref. FCT UID/AMB/50017/2013), CIIMAR (Ref. FCT UID/Multi/04423/2013) financed by national funds through the FCT/MEC and co-financed by FEDER under the PT2020 Partnership Agreement, and Program Investigador FCT. Authors are also grateful to the National Network of electron microscopy and University of Aveiro: Project REDE/1509/RME/2005. MAOL and CBL acknowledge, respectively, the Grants SFRH/BD/80883/2011 and SFRH/BPD/99453/2014.