摘要
Cordierite monoliths coated with Pd-Fe/a- Al2O3 catalysts were prepared at various calcination temperatures and characterized by thermogravimetry, temperature-programmed reduction, transmission electron microscopy, diffuse reflectance infrared Fourier transfor- mation spectroscopy and X-ray diffraction. The performance of the catalytic monoliths for the synthesis of dimethyl oxalate （DMO） through a CO coupling reaction was evaluated. Monolithic catalysts with calcination temperatures ranging from 473 K to 673 K exhibited excellent dispersion of Pd, good CO adsorption properties, and excellent performance for the coupling reaction. The optimized monolithic catalyst exhibited a much higher Pd efficiency （denoted as DMO （g）.Pd （g）-1 h 1） （733h-1） than that of the granular catalyst （60.2 h-1）, which can be attributed to its honeycomb structure and the large pore sizes in the a-Al2O3 washcoat which was accompanied with an even distribution of the active component in the coating layer along the monoliths channels.
Cordierite monoliths coated with Pd-Fe/a- Al2O3 catalysts were prepared at various calcination temperatures and characterized by thermogravimetry, temperature-programmed reduction, transmission electron microscopy, diffuse reflectance infrared Fourier transfor- mation spectroscopy and X-ray diffraction. The performance of the catalytic monoliths for the synthesis of dimethyl oxalate （DMO） through a CO coupling reaction was evaluated. Monolithic catalysts with calcination temperatures ranging from 473 K to 673 K exhibited excellent dispersion of Pd, good CO adsorption properties, and excellent performance for the coupling reaction. The optimized monolithic catalyst exhibited a much higher Pd efficiency （denoted as DMO （g）.Pd （g）-1 h 1） （733h-1） than that of the granular catalyst （60.2 h-1）, which can be attributed to its honeycomb structure and the large pore sizes in the a-Al2O3 washcoat which was accompanied with an even distribution of the active component in the coating layer along the monoliths channels.
