Dynamic hydrogen production from ethanol steam-reforming reaction on Ni_xMo_y/SBA-15 catalytic system

Abstract

SUMMARYThis study examined the effects of advanced bimetallic catalytic species of Ni and Mo on hydrogen production from ethanol steam reforming. Ni x Mo y /SBA-15 exhibited significantly higher ethanol steam-reforming activity at mild temperatures than monometallic Ni/SBA-15; the highest activity was achieved using the Ni 0.95 Mo 0.05 /SBA-15 catalyst. H 2 production and ethanol conversion were maximized at 70-87% and 90-92%, respectively, over the temperature range of 500 to 800°C with an EtOH : H 2 O ratio of 1:3 and a gas hourly space velocity of 3000 h À1 . This highlights the synergy between the Ni and Mo loading on SBA-15 during ethanol steam reforming through the inhibition of Ni particle agglomeration and the consequent decrease in catalytic deactivation. In the proposed mechanism for ethanol steam reforming, Mo oxide promotes CH 4 -steam reforming at lower temperatures and depresses the CO-water gas shift reaction. Overall, hydrogen production is significantly higher over Ni x Mo y /SBA-15 than over monometallic Ni/SBA-15 despite the evolution of CO gas.

Ethanol steam reforming on Ni/CaO catalysts for coproduction of hydrogen and carbon nanotubes

“…When the Ni loading further increases to 40%, there is a slight increase of CH 4 yield. In a study of Kim et al, 30% Ni/SBA‐15 catalyst, S/C ratio of 1.5, and 550°C to 800°C temperature range have been employed for ethanol steam reforming, and the corresponding hydrogen yield could reach about 70% at 700°C. Wu et al obtained a maximum hydrogen yield of 72.0% at 20% Ni/SiO 2 catalyst, S/C ratio of 4, and reforming temperature of 600°C from ethanol steam reforming.…”

“…In this regard, higher activity and lower cost make suitable choice for using the nickel‐based catalysts to produce H 2 through steam reforming process. Many kinds of catalyst supports, ie, SiO 2 , montmorillonite, ZnO, ceramic foam, and SBA‐15 have been investigated for Ni catalytic steam reforming . The characteristics of Ni catalysts are considered to be affected by the chemical composition and the physical structure of catalyst support.…”

“…Many kinds of catalyst supports, ie, SiO 2 , montmorillonite, ZnO, ceramic foam, and SBA-15 have been investigated for Ni catalytic steam reforming. 5,9,10 The characteristics of Ni catalysts are considered to be affected by the chemical composition and the physical structure of catalyst support.…”

A survey of nickel-based catalysts and monolithic reformers of the onboard fuel reforming system for fuel cell APU applications

“…As for the support materials, the most commonly used supports are α‐Al 2 O 3 , γ‐Al 2 O 3 , SiO 2 , MgO, MgAl 2 O 4 , CeO 2 , ZrO 2 , etc. . Surface acid sites presented in the supports may promote carbon formation on the catalyst surface , so that the supports with relatively low concentrations of Lewis acid sites such as MgO, ZrO 2 , and La 2 O 3 can lower the coke deposition rate .…”

The steam reforming of guaiacol for hydrogen via Ni/Al 2 O 3 : The influence of dispersion

“…The choice of catalyst is the key to improve the conversion of phenols. Ni‐based catalysts are often used for steam reforming due to their strong catalytic activity . However, it has been found that due to the complex composition of phenols, the strong acid sites of Ni‐based catalysts tend to cause large amounts of reactants to adsorb on the surface and coking, which lead to catalyst deactivation.…”