Platinum-Copper Bimetallic-Modified Nanoprism Mordenite for Carbonylation of Dimethyl Ether

Platinum-copper bimetallic-modified mordenite catalysts for the dimethyl ether (DME) carbonylation to methyl acetate (MA) were carried out using a laboratory-made nanoprism mordenite, which was synthesized by hydrothermal method and modified by ion exchange with Cu(NO3)(2) and wet impregnation with H2PtCl6. The catalyst was characterized by X-ray diffraction, inductively coupled plasma atomic emission spectroscopy, N2O titration, NH3 temperature-programmed desorption, H-2 temperature-programmed reduction, pyridine-infrared, Fourier transform infrared, Brunauer-Emmett-Teller, high-resolution transmission electron microscopy, energy-dispersive spectrometry mapping, scanning electron microscopy, X-ray photoelectron spectroscopy, and temperature-programmed oxidation. Bimetallic platinum-copper catalysts exhibited high catalytic activity for carbonylation of DME, which was attributed to the large quantity of the Bronsted acid sites in the eight-membered ring (8-MR). Moreover, the bimetallic catalyst with small copper particle size and bimetallic synergism promoted conversion of DME and MA selectivity. Over the 1Pt/Cu-mor catalyst (1 wt % Pt and 2 wt % Cu), DME conversion and MA selectivity reached 86.0% and 96.0%, respectively. What's more, the addition of Pt reduced the acidity of the 12-membered ring (12-MR) in the Cu-mor catalyst, resulting in a suppression of hard coke formation.