화학공학소재연구정보센터
Chemical Engineering Journal, Vol.272, 108-118, 2015
Glycerol steam reforming over layered double hydroxide-supported Pt catalysts
Layered double hydroxides containing Mg and Al (Mg/Al ratios of 3 and 5) were used as support for Pt-based catalysts for glycerol steam reforming. Additionally, catalysts supported on the parent MgAl mixed oxides were also evaluated. Fresh catalyst samples were characterized by XRD, BET, TPD-CO2 and XRF whilst the spent catalysts were examined by TEM and TPO/TGA-MS. All catalysts revealed to be active, leading to a hydrogen-rich gas stream but with distinct resistance to deactivation. The catalyst synthesized directly from the layered double hydroxide precursors with Mg/Al ratio of 3 was shown to be more effective since global and gas conversion are similar, varying within 60-25%. Major incidence of weak to moderate basic surface centers rendered catalysts more selective, reaching up to 68% selectivity to hydrogen. However, they were not enough to suppress deactivation. It was found that the formation of more stable carbon deposits play a key role on deactivation and only a minor contribution from the carbonaceous material formed from the intermediate organic liquid compounds was proposed. Highly dispersed metal centers were suggested to be important for in situ catalyst surface cleanness. (C) 2015 Elsevier B.V. All rights reserved.