Applied Catalysis A: General, Vol.541, 15-24, 2017
Catalytic oxidative dehydrogenation of carveol to carvone over the phthalocyanine complex FePcCl16 immobilized on the mesoporous silica SBA-15
The immobilization of the FePcCl16 complex on the mesoporous silica SBA-15 and its performance in the eco-friendly oxidative dehydrogenation of carveol to carvone in the presence of t-butyl hydroperoxide (TBHP) under mild conditions is reported. The successful covalently anchored of FePcCl16 complex inside the pores of SBA-15, without complex or support damage, was confirmed by XRD, BET, UV-vis, SEM, TEM and Raman analysis. The best results achieved were after 1 h of reaction, with 40% carvone selectivity and a carveol conversion around of 75%; carvone selectivity decayed when carveol conversion increased. Several mechanisms and rate equations derived from the kinetic models based on the Power Law, Langmuir-Hinshelwood, and Eley-Rideal model were proposed. Although the Power Law model showed the best mathematical fitting, the Eley-Rideal model seems to explain better the chemical sense of reaction. FePcCl16-NH2-SBA-15 catalyst was stable under the reaction conditions and it can be used up to twice without significant decrease in its catalytic activity.