Systematic Investigation on Supported Gold Catalysts Prepared by Fluorine-Free Basic Etching Ti3AlC2 in Selective Oxidation of Aromatic Alcohols to Aldehydes.

Abstract

Conventional methods to prepare supported metal catalysts are chemical reduction and wet impregnation. This study developed and systematically investigated a novel reduction method based on simultaneous Ti3AlC2 fluorine-free etching and metal deposition to prepare gold catalysts. The new series of Aupre/Ti3AlxC2Ty catalysts were characterized by XRD, XPS, TEM, and SEM and were tested in the selective oxidation of representative aromatic alcohols to aldehydes. The catalytic results demonstrate the effectiveness of the preparation method and better catalytic performances of Aupre/Ti3AlxC2Ty, compared with those of catalysts prepared by traditional methods. Moreover, this work presents a comprehensive study on the influence of calcination in air, H2, and Ar, and we found that the catalyst of Aupre/Ti3AlxC2Ty-Air600 obtained by calcination in air at 600 °C performed the best, owing to the synergistic effect between tiny surface TiO2 species and Au NPs. The tests of reusability and hot filtration confirmed the catalyst stability.