Abstract (EN):
Copper(II) acetylacetonate was anchored onto a triamine functionalised activated carbon by Schiff condensation using a four-step procedure: (i) oxidation of activated carbon with nitric acid; (ii) treatment with thionyl chloride to convert Carbon surface carboxylic acids into acyl chlorides; (iii) condensation of acyl chloride functionalities with amine groups of bis(3-aminopropyl)amine (trien); and (iv) Schiff condensation between free amine groups of bound trien with the oxygen atoms of acetylacetonate coordinated to the copper(ii) ion. The same complex was also anchored to the unmodified activated carbon and to the acyl chloride functionalised carbon prepared in (ii). The resulting carbon-based materials were characterised by elemental analysis, surface techniques (SEM and XPS), temperature programmed desorption, and nitrogen adsorption at 77 K and EPR spectroscopy for the materials with copper(ii) complexes. Data from all techniques provided evidence for (i) the covalent binding of trien to acyl chloride functionalities; and (ii) the irreversible attachment of [Cu(acac)(2)] to all carbon-based materials. Data for the materials with copper(II) proved conclusively that only the immobilisation procedure based on Schiff condensation with trien led to copper(II) complexes in which the metal centre remains four-coordinate. (C) Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004.
Idioma:
Inglês
Tipo (Avaliação Docente):
Científica
Contacto:
acfreire@fc.up.pt
Nº de páginas:
9