abstract
Layered materials including metal phosphates and phosphonates have been widely investigated in several fields acting as good selective catalysts in a great number of oxidative reactions. Zirconium phosphate amorphous [Zr(HPO4)(2)center dot H2O; ZrPA], sodium exchanged zirconium phosphate amorphous [Zr(NaPO4)(2); NaZrPA], potassium exchanged zirconium phosphate amorphous [Zr(KPO4)(2); KZrPA], zirconium phenylphosphonate amorphous [Zr(O3PC6H5)(2); ZrPPA], zirconium carboxyethylphosphonate [Zr(O3PCH2CH2COOH)(2); ZrCEP] and aluminium carboxyethylphosphonate [Al-3(OH)(3)(O3PCH2CH2CO2)(2)center dot 3H(2)O; AlCEP] were prepared, characterized and evaluated as selective catalysts in the Baeyer-Villiger oxidation of cyclopentanone, p-methoxybenzaldehyde and 2,4,6-trimethylbenzaldehyde by hydrogen peroxide, in acetic acid. The selectivity of delta-valerolactone, p-methoxyphenol and 2,4,6-trimethylphenol have been found to be strongly related with the properties and structure of each catalyst.
keywords
LAYERED ZIRCONIUM-PHOSPHATE; INSOLUBLE ACID SALTS; HYDROGEN-PEROXIDE; AROMATIC-ALDEHYDES; CRYSTAL-STRUCTURES; HETEROGENEOUS CATALYSIS; HYDROTALCITE CATALYSTS; TETRAVALENT METALS; BASE CATALYST; IONIC LIQUIDS
subject category
Chemistry
authors
Rocha, GMSRO; Santos, TM; Bispo, CSS
our authors
Cláudia Sofia dos Santos Bispo
PhD Student
Teresa Margarida dos Santos
Retired Professoracknowledgements
The authors would like to thank the Chemistry Department and CICECO (Centre for Research in Ceramics and Composites Materials), University of Aveiro, for support.