Stabilizing copper species using zeolite for ethanol catalytic dehydrogenation to acetaldehyde

The selective dehydrogenation of ethanol to acetaldehyde is a promising route for acetaldehyde production. Although Cu-based catalysts exhibit high activity in ethanol dehydrogenation, a rapid deactivation due to Cu sintering always occurs. In this study, highly dispersed Cu species were sta-bilized using the silanol defects in Beta zeolite (denoted as Beta) resulting from dealumination, and applied as robust catalysts for ethanol-to-acetaldehyde conversion. Typically, a long catalyst life-time of 100 h with an acetaldehyde yield of ∼70% could be achieved over 5% Cu/Beta. The pres-ence of Cu+ and Cu0 species and the agglomeration of Cu particles after a long-term reaction for 180 h were revealed by transmission electron microscopy, thermogravimetric analysis, and CO-diffuse-reflectance infrared Fourier transform spectroscopy, and were responsible for the deac-tivation of the Cu/Beta catalyst in the ethanol-to-acetaldehyde conversion.