H3PW12O40/mpg-C3N4 as an efficient and reusable catalyst in the alkylation of o-xylene and styrene

A heterogeneous catalyst (HPW/mpg-C3N4) for the alkylation of o-xylene and styrene reaction was acquired by the immobilization of phosphotungstic acid (HPW) on mesoporous graphitic carbon nitride (mpg-C3N4) through electrostatic interaction. The results of Fourier transform infrared spectroscopy (FT-IR), X-ray powder diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and thermogravimetric analysis (TGA) proved that HPW was successfully immobilized on the protonated mpg-C3N4 by electrostatic interaction. The textural properties and morphology of HPW/mpg-C3N4 were characterized by N-2 adsorption-desorption, scanning electron microscopy (SEM). Among them, 40% HPW/mpg-C3N4 displays the best catalytic performance in the alkylation reaction with 91.8% yield and 96.5% selectivity to 1, 2-diphenylethylane. Moreover, protonated mpg-C3N4 not only displays as a support to facilitate great dispersion of HPW but also promotes the alkylation product diffusion effectively. Besides, the HPW/mpg-C3N4 catalyst could be recycled easily without significant loss of catalytic activity, which is demonstrate by the recyclability of HPW/mpg-C3N4 catalyst test.