Potential applications of highly ordered mesoporous materials in analytical chemistry and the environment

• Grant number: 07/07646-2
• Support type: Scholarships in Brazil - Post-Doctorate
• Effective date (Start): May 01, 2008
• Effective date (End): April 30, 2010
• Field of knowledge: Physical Sciences and Mathematics - Chemistry - Analytical Chemistry
• Principal researcher: Jorge Cesar Masini
• Grantee: Luís Carlos Cides da Silva
• Home Institution: Instituto de Química (IQ). Universidade de São Paulo (USP). São Paulo , SP, Brazil

Abstract

In this project we will study the synthesis, characterization and potential environmental and analytical applications of pure and modified highly ordered mesoporous silica materials having cubic 3D structure, with high thermal and hydrothermal stability. The silica FDU-1 is prepared in strongly acidic media using tetraethylorthosilicate (TEOS) as the silica source. Triblock copolymers, B50-6600 (EO39BO47EO39) and Vorasurf 504® (PEO-PBO-PEO), will be used as template. A first modification will be made, using humic acid in proportions previously established, to assemble a pre-concentration column for retention of mercury ions. The surface modification by Grafting will be made using APMES and APTES as silylant agents. These modified silica materials will be studied for adsorption of Cu2+, Pb2+ and Cd2+ ions, in comparison with the pristine FDU-1 silica. Modified silica will be prepared by incorporating crystalline zeolites on the silica walls (FDU-1/ZSM-5) aiming adsorption of triazines, as well as to perform degradation studies of these aromatic compounds exploring the catalytic properties of the modified silica. Synthesis and characterization of hybrid organic-inorganic periodic mesoporous structures (PMOs) will be made using the triblock copolymer Vorasurf 504® in strongly acidic media, followed by hydrothermal treatment in a microwave oven. This material will be used to assess the adsorption capacity of Cd2+, Cu2+, Pb2+ and Hg2+ ions. The gels of synthesis will be submitted to hydrothermal treatment in oven or microwave oven, and then the samples will be calcinated in atmosphere of N2 and air, or submitted to solvent extraction. The materials will be characterized by thermogravimetry/derivative thermogravimetry (TG/DTG), elemental analysis (EA), infrared spectroscopy absorption (IR), small angle X-ray diffraction (SAXRD), transmission electron microscopy (TEM), N2 adsorption isotherms. The determinations of ions and organic compounds will be carried out by voltammetry methods and/or automated sequential injection chromatography.

Scientific publications

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

CIDES DA SILVA, LUIS CARLOS; INFANTE, CARLOS M. C.; DE PRA URIO, RICARDO; COSENTINO, IVANA CONTE; DE ABREU FANTINI, MARCIA CARVALHO; MATOS, JIVALDO DO ROSARIO; DO NASCIMENTO, FERNANDO H.; MASINI, JORGE C.. Adsorption/Desorption of Hg(II) on FDU-1 Silica and FDU-1 Silica Modified with Humic Acid. SEPARATION SCIENCE AND TECHNOLOGY, v. 50, n. 7, p. 984-992, MAY 3 2015. (07/07646-2)

CIDES DA SILVA, L. C.; INFANTE, C. M. C.; LIMA, A. W. O.; COSENTINO, I. C.; FANTINI, M. C. A.; ROCHA, F. R. P.; MASINI, J. C.; MATOS, J. R.. Immobilization of glucose oxidase enzyme (GOD) in large pore ordered mesoporous cage-like FDU-1 silica. JOURNAL OF MOLECULAR CATALYSIS B-ENZYMATIC, v. 70, n. 3-4, p. 149-153, JUL 2011. (08/09284-3, 07/07646-2)

CIDES DA SILVA, L. C.; DOS REIS, T. V. S.; COSENTINO, I. C.; FANTINI, M. C. A.; MATOS, J. R.; BRUNS, R. E.. Factorial design to optimize microwave-assisted synthesis of FDU-1 silica with a new triblock copolymer. Microporous and Mesoporous Materials, v. 133, n. 1-3, p. 1-9, SEP 2010. (07/07646-2)