Aqueous-phase reforming of xylitol over Pt/C and Pt/TiC-CDC catalysts: catalyst characterization and catalytic performance

Abstract

aThe aqueous phase reforming (APR) of xylitol was studied over five Pt/C catalysts. The correlation between physico-chemical properties of the catalysts and catalytic performance was established. The Pt/C catalysts have different textural properties as well as different mean Pt cluster sizes and surface acidity. The average Pt cluster size was investigated by means of CO chemisorption as well as by TEM.The reaction was found to be structure sensitive and TOF linearly increases with increasing average Pt cluster size in the studied domain. The catalysts which possess higher surface acidity favoured higher rates of hydrocarbon production. On the contrary the Pt/C materials with lower acidities generated hydrogen with high selectivity and TOF.

Aqueous phase reforming of ethylene glycol on Pt/CeO2–ZrO2: effects of cerium to zirconium molar ratio

“…In addition, the EG conversions to hydrocarbons on the Pt/CeO 2 -ZrO 2 were observed to be below 0.8%, except for Pt/ZrO 2 with a conversion of 2.1%. As reported in previous work, 16 the APR of polyols for hydrogen production is a structure-sensitive reaction, with a linear increase in intrinsic activity with the increase in average platinum cluster size, and acid sites on the catalyst surface are favorable for the hydrocarbon formation instead of hydrogen. Therefore, the observed higher conversion of EG and lower selectivity for CO on Pt/CeO 2 -ZrO 2 (4) seems to be mainly attributed to the formation of small platinum crystallites.…”

Production of bio-hydrogen by liquid processing of xylitol on Pt/Al2O3 catalysts: Effect of the metal loading

“…At WHSV ¼ 2 h À1 , 493 K, 28 atm, and 10% xylitol, Kim et al [19] yielded 18 mmol H 2 /g cat h À1 on Pt(7%)/ carbon. When Pt was supported on supports more acid than alumina such as TiO 2 , carbon or zeolites, the H 2 productivity by APR of xylitol was significantly lower than the maximum Pr value reported in this work [16,17].…”

“…Kirilin et al [15] investigated the production of H 2 by APR of xylitol on Pt(5%)/ Al 2 O 3 at 498 K, 29.3 bar and 10 wt.% xylitol in the feed, using space velocities between 1.2 and 3.9 h À1 ; they obtained a maximum H 2 yield of 32% at WHSV ¼ 1.8 h À1 . Kim et al [19] studied the APR of 10% xylitol at WHSV ¼ 2 h À1 on 7% Pt/ carbon using different pressures (28e45 bar) and temperatures (493e523 K); they reported a maximum h H2 value of 35.4% at 523 K and 45 bar.…”

Sibunit-Supported Mono- and Bimetallic Catalysts Used in Aqueous-Phase Reforming of Xylitol

“…Just two publications fall into this category. Namely, Kirilin et al 50 studied the APR of xylitol over 2.8% Pt/CDC. The observed conversion was 12% at WSHV = 3 h –1 , while in the current study much higher values were obtained: 48% at WSHV = 2.4 h –1 over 3% Pt/C and 51% at WSHV = 3 h –1 over the commercial 2.5% Pt/C.…”