The Activity of Fe-Pd Alloys for the Water-Gas Shift Reaction
نویسندگان
چکیده
The role of Fe promoters has been investigated on Pd/ceria, Pt/ceria and Rh/ceria catalysts for the water-gas shift (WGS) reaction in 25 Torr of CO and H2O, under differential reaction conditions. While no enhancement was observed with Pt and Rh, the activity of Pd/ceria increased by as much as an order of magnitude upon the addition of an optimal amount of Fe. Similarly, the addition of 1 wt% Pd to an Fe2O3 catalyst increased the WGS rate at 453 K by a factor of 10 over that measured on Fe2O3 alone, while the addition of Pt or Rh to Fe2O3 had no effect on rates. The amount of Fe that was necessary to optimize the rates increased with Pd loading but was independent of the order in which Fe and Pd were added to the ceria. Increased WGS activity was also observed upon the addition of Fe to Pd supported on Ce0.5Zr0.5O2. XRD measurements, performed after running the catalyst under WGS conditions, show the formation of a Fe-Pd alloy, even though similar measurements on an Fe/ceria catalyst showed that Fe3O4 was the stable phase for Fe in the absence of Pd. Possible implications of these results on the development of new WGS catalysts are discussed.
منابع مشابه
Kinetic Modeling of the High Temperature Water Gas Shift Reaction on a Novel Fe-Cr Nanocatalyst by Using Various Kinetic Mechanisms
In this work the kinetic data demanded for kinetic modeling were obtained in temperatures 350, 400, 450 and 500 oC by conducting experimentations on a Fe-Cr nanocatalyst prepared from a novel method and a commercial Fe-Cr-Cu one. The collected data were subjected to kinetic modeling by using two models derived from redox and associative mechanisms as well as an empirical one. The coefficients o...
متن کاملEffect of MgAl2O4 catalyst support synthesis method on the catalytic activity of nickel Nano catalyst in reverse water gas shift reaction
In this research effect of synthesis method of magnesium aluminate as support of Ni catalysts at the reverse water gas shift (RWGS) reaction was evaluated. The RWGS reaction is applied in Carbon Dioxide Hydrogenation to Form Methanol via a Reverse Water-Gas Shift Reaction (CAMERE) process for the transformation of CO2 into methanol. The MgAl2O4 supports were prepared by sol-gel (M1), surfactant...
متن کاملThe Effect of Fe and Other Promoters on the Activity of Pd/Ceria for the Water-Gas Shift Reaction
The effect of adding oxide promoters, at monolayer coverages, to Pd/ceria catalysts was studied for the watergas-shift reaction in 25 torr each of H2O and CO under differential conditions. Oxides of Fe, Tb, Gd, Y, Sn, Sm, Pr, Eu, Bi, Cr, V, Pb, and Mo were added to ceria by wet impregnation of aqueous salts and calcined to 873 K prior to addition of 1 wt% Pd. While most of the oxides had a negl...
متن کاملEffect of Water Gas Shift Reaction on the Non-Isothermal Reduction of Wustite Porous Pellet Using Syngas
Effect of water gas shift reaction (CO+H2O=CO2+H2) on wustite reduction has been investigated by a transient, non-isothermal mathematical model based on grain model. In this model, wustite porous pellet is reduced using Syngas, namely a mixture of hydrogen, carbon monoxide, carbon dioxide and water vapor. For this purpose, governing equations containing continuity equation of species and energy...
متن کاملBioreactor Scale-up for Water-Gas Shift Reaction
A scale-up study has been performed with three different size reactors to establish the optimum operating conditions for the hydrogen production from synthesis gas by biological water-gas shift reaction using the photosynthetic bacterium Rhodosprilliunt rubrum. Optimum medium composition and operating conditions previously determined in a bench scale 1.25 L continuous stirred tank reactor (CSTR...
متن کامل