H₂Production by Autothermal Reforming ofn-Dodecane over Highly Active Ru–Ni–Ce–Al₂O₃Catalyst

Abstract

Autothermal reforming of n-dodecane, a main constituent of jet fuel, over Ru-promoted nickel–ceria–alumina-based catalyst was carried out in a fixed-bed microreactor operating at atmospheric pressure. The temperature was varied from 873 to 1073 K, space velocity range was 96000–480000 h–1, and H2O/C molar ratio in the feed was between 1.5 and 4.0. The monometallic and bimetallic catalysts were prepared by the sol–gel method. X-ray diffraction (XRD), BET surface area, temperature-programmed reduction (TPR), and temperature-programmed desorption of H2 (TPD of H2) were used to characterize the prepared catalysts. Characterization results reveal that the presence of Ru and CeO2 enhances the catalyst reducibility. H2-TPD data indicate that Ru-promoted Ni–Ce–Al2O3 catalyst exhibits larger nickel surface area compared to monometallic Ni and Ru catalysts. The activity and hydrogen yield on the Ru-promoted Ni–Ce–Al2O3 catalyst was observed to be significantly higher than those on the monometallic catalysts under the same experimental conditions.

Ni-based bimetallic heterogeneous catalysts for energy and environmental applications

“…It has been proved that carbon formation occurs less on noble metals than on Ni, mainly because the lower solubility of carbon in noble metals favors the gasification of carbon. In fact, many previous works have reported that Ni catalysts can exhibit high efficiency and better resistance against carbon deposition when modified with noble metals such as Pd, 74 Pt, [75][76][77][78][79][80][81][82][83] Ru, 84,85 Rh, [86][87][88][89][90][91] Ir, 92 Au, [93][94][95][96][97] and Ag. [98][99][100] The effects of these secondary noble metals are diverse; they may function to reduce and stabilize the metal particle size of the Ni catalysts (e.g.…”

Oxidative Steam Reforming and Steam Reforming of Methane, Isooctane, and N-Tetradecane over an Alumina Supported Spinel-Derived Nickel Catalyst

“…Indeed under these more favorable conditions a wide number of works reported reforming efficiencies for C 12 –C 16 fuels in the range 60–100% over nickel catalysts. In this sense Gugilla et al found a 60% conversion ( n -dodecane) over a 10%Ni/CeO 2 /Al 2 O 3 at 750 °C and 2400 cm 3 n- C 12 H 26 g –1 h –1 . Substantially higher conversions (in the 90–100% range) are obtained with a lower VHSV by Kaila et al over a 12 wt % Ni/Al 2 O 3 catalyst at 700 °C and 980 cm 3 n- C 12 H 26 g –1 h –1 ( n -dodecane) and Xie et al with a 5 wt % Ni/CeO 2 catalyst at 750 °C and 1500 cm 3 n- C 16 H 34 g –1 h –1 ( n -hexadecane).…”

“…These authors observed a marked decrease in conversion from 65% to 40% in the steam reforming of this fuel at 800 °C and a molar H 2 O/C ratio of 2 over a 1 wt % Ru/10%Ni/CeO 2 /Al 2 O 3 catalyst . However, when oxygen is added to the feed stream (O/C = 0.35), both catalytic activity and stability at the same reaction temperature are promoted, since an almost constant higher conversion (70%) is obtained for 10 h time on stream …”

“…44 However, when oxygen is added to the feed stream (O/C = 0.35), both catalytic activity and stability at the same reaction temperature are promoted, since an almost constant higher conversion (70%) is obtained for 10 h time on stream. 37 The product distribution for steam reforming is only stable for methane. A moderately lower H 2 yield (0.43, which corresponds to 71% of the equilibrium value) is obtained over the nickel catalyst with respect to OSR.…”

Enrichment of Hydrogen Production from Biomass‐Gasification‐Derived Syngas over Spinel‐Type Aluminate‐Supported Nickel Catalysts

“…Among transition‐metal‐oxide‐supported catalysts, Ni‐based catalysts have been effective in the production of H 2 ‐enriched products . Al 2 O 3 is a common material used as a support for these catalytic reactions because of its advantageous large surface area and high mechanical strength . A 7Ni‐2Cu/Al 2 O 3 catalyst promoted biomass‐gasification‐derived syngas with enhanced H 2 production .…”