Elucidation of the roles of Re in steam reforming of glycerol over Pt–Re/C catalysts

Abstract

In this paper, we report the fundamental understanding of surface properties of Pt/C and Pt-Re/C catalysts and their correlation with catalytic performance in steam reforming of glycerol. We found that the addition of Re increases the catalytic activity, H 2 /CO x ratio and CO 2 selectivity. N 2 physisorption, CO chemisorption, attenuated total reflectance infrared (ATR-IR), Raman and Xray absorption spectroscopy (XAS) with in situ capabilities were employed to provide the insights into the roles of Re. Using ATR-IR, we show that CO adsorption

Evidence for the Bifunctional Nature of Pt–Re Catalysts for Selective Glycerol Hydrogenolysis

“…Therefore, the oxidation state of Re depends on the pretreatment of the catalyst and the conditions under which the catalyst is probed. 35 Recently, in situ X-ray absorption spectroscopy (XAS) has been used to study Pt-Re particles supported on Norit carbon 4 as well as Rh-Re 40 and Ir-Re 41 particles supported on silica.…”

Investigation of the promoting effect of Mn on a Pt/C catalyst for the steam and aqueous phase reforming of glycerol

“…Detailed ATR-IR experiments are described in our previous report [17]. The Internal Reflection Element (IRE) was coated by suspending 5 mg of catalyst in 1 mL of Milli-Q water, and sonicating the solution for 30 s. Continuously, 400 μL of solution were deposited on the surface of the IRE.…”

“…In this scenario, glycerol will become one of the most important commodities as it is the main byproduct from the transesterification of vegetable oils and fats to produce biodiesel, and is a good model compound for polyols in biomass catalytic conversion processes [14][15][16]. Many works have been published on SR and APR of glycerol for the hydrogen production, using a variety of catalysts based on both precious and non-precious metals [11,[17][18][19][20][21][22][23][24].…”

“…The authors found an increased glycerol conversion, but a lower hydrogen selectivity, ascribed to the partial oxidation of Mo in APR conditions, which led to increased C-O cleavage activity through acid catalyzed reactions [21]. As one of the early effective industrial promoters used in particular for the naphtha reforming, Re has attracted much attention also for the reforming of other substrates other than glycerol, like ethylene glycol, phenols, and sugars [11,12,17,24,26]. Generally, the catalytic performances of the Pt-Re catalysts increased with all the substrates, both in SR and APR.…”

“…Generally, the catalytic performances of the Pt-Re catalysts increased with all the substrates, both in SR and APR. Besides the acidity induced by the partial oxidation of Re in hydrothermal conditions, which as in the case of Mo led to higher conversion levels but lower selectivity toward hydrogen, Wang and co-workers found that the enhanced performances of Pt-Re catalysts were mostly due to the facile CO desorption from the catalyst surface by spillover from Pt to adjacent ReO x sites, thus explaining the low activation energy for CO production found by Kunkes et al [11,17,24,27,28].…”