Synthesis and catalytic activity of different substituted metal phthalocyanine-MWCNTs hybrid materials for selective oxidation of styrene

Abstract

ABSTRACTAn efficient process for the preparation of novel [4α(OPh-t-Bu)MPc]-MWCNTs and tetranitro substituted metal phthalocyanine (MTNPc)-MWCNTs hybrid catalysts was developed via an ultrasonic impregnation method. The obtained hybrid materials were characterized comprehensively with X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and Fourier transform infrared spectra (FT-IR). The oxidation of styrene was examined using tert-Butyl hydroperoxide (TBHP) as oxidant, and using MTNPc-MWCNTs and [4α(OPh-t-Bu)MPc]-MWCNTs complexes (M: Zn and Co) as catalysts. The results indicated that cobalt phthalocyanines were more efficient catalysts in the styrene oxidation reaction as compared to zinc phthalocyanine. It was found that during reaction with tert-butyl hydroperoxide (TBHP) as the oxidant, the conversion and selectivity of all synthesized compounds in dimethylformamide (DMF) was higher than in acetonitrile (CH3CN). Moreover, the catalytic mechanism of styrene oxidation has been proposed for the different substituted metal phthalocyanine-MWCNTs hybrid materials.