Composite Structured M/Ce0.75Zr0.25O2/Al2O3/FeCrAl (M = Pt, Rh, and Ru) Catalysts for Propane and n-Butane Reforming to Syngas

Abstract

Here, we report the preparation, characterization, and performance of reforming propane and n-butane into a syngas of composite structured M/Ce0.75Zr0.25O2/Al2O3/FeCrAl (M = 0.46 wt.% Pt, 0.24 wt.% Rh, and 0.24 wt.% Ru) catalysts. The catalysts are composed of a high-heat-conducting FeCrAl block with preset geometry, with a surface nearly totally covered by θ-Al2O3. Afterwards, a layer of ceria–zirconia mixed oxide was deposited. The formed oxide coating was used as a support for 2–3 nm sized Pt, Rh, or Ru nanoparticles. The performance of the catalysts in propane steam reforming decreased in the order of Rh ≈ Ru > Pt. The reformates obtained in the propane steam reforming over Rh- and Ru/Ce0.75Zr0.25O2/Al2O3/FeCrAl at 600 °C and GHSV = 8300 h−1 contained 65.2 and 62.4 vol.% of H2, respectively, and can be used as a fuel for solid oxide fuel cells. In the oxidative steam reforming of propane at 700 °C and GHSV= 17,000 h−1, the activities of the Rh- and Pt-based catalysts were similar and the compositions of the outlet gas mixtures were quite close to equilibrium in both cases. Increasing the reagent flow rate to 25,600 h−1 showed stability of the Rh/Ce0.75Zr0.25O2/Al2O3/FeCrAl performance, whereas the Pt/Ce0.75Zr0.25O2/Al2O3/FeCrAl activity decreased. A mathematical model considering the velocity field, mass balance, pressure, and temperature distribution, as well as the reaction kinetics, was suggested for the propane steam and oxidative steam reforming over the Pt- and Rh/Ce0.75Zr0.25O2/Al2O3/FeCrAl catalysts. The model well described the experimental results.

Molten salt synthesis of CrMnFeNi alloy nanopowder passivated by TiOx–ZrOy shell used as a superior catalyst support in liquid-phase hydrogenation

“…The aluminum oxide surface shell formed by an initial oxidation treatment of the alloys protects from further inner oxidation, thus allowing FeCrAl alloy support to be available under high-temperature reaction conditions. To date, FeCrAl alloy supports have been used in several catalytic reactions involving methane oxidation, [3][4][5][6][7][8] selective catalytic reduction (SCR) of NO x , 9 CO oxidation, 10 methanation, 11 reforming, [12][13][14][15][16] and Fischer-Tropsch synthesis. 17 In our previous work, we used an intermetallic compound Ti 6 Si 7 Ni 16 with a high specic surface area (37.5 m 2 g −1 ) as catalyst support in CO methanation.…”

Editorial for Special Issue “Advanced Materials in Catalysis and Adsorption”

“…The functionalization of CNMs with heteroatoms (i.e., nitrogen [ 1 , 6 , 7 , 8 ] and boron [ 3 ]) is an effective method for boosting the applicability of carbon nanomaterials as catalytic substrates. Another group of the designed materials belongs to the oxide-based supports, including zeolite catalysts [ 9 ], composite catalytic materials [ 5 , 10 , 11 , 12 ], mixed Mn-Zr-Ce-O oxides [ 13 ], and perovskite-like materials [ 14 ]. In many cases, the active component of the developed catalysts is represented by precious metals—Pd [ 1 , 7 ], Pt [ 5 , 11 ], Rh [ 10 , 11 ], and Ru [ 11 ]—and other metals such as Ag [ 15 ], Au [ 7 , 9 ], and their alloys.…”

“…Advanced catalytic materials have been developed for diverse types of heterogeneous catalytic reactions, such as the hydrodechlorination of chloroaromatics [ 1 ]; the dehalogenation of halogenated hydrocarbons [ 2 ]; dechlorination via catalytic pyrolysis [ 1 , 2 , 4 ]; the catalytic coupling of CH 4 [ 14 ]; the catalytic processing of hydrocarbons and their mixtures into synthesis gas [ 10 , 11 ] or CNT and CNF materials [ 2 , 5 , 6 , 8 ]; the oxidation of carbon monoxide [ 13 ]; the hydrogenation of organic compounds [ 7 ]; and selective oxidation [ 9 ]. Such advanced materials can be also used for electrocatalytic applications involving the oxygen evolution reaction (OER) [ 12 ] and the electrocatalytic reduction of carbon dioxide (CO 2 RR) [ 15 ].…”

“…The composite structured catalysts M/Ce 0.75 Zr 0.25 O 2 /Al 2 O 3 /FeCrAl (M = Pt, Rh, Ru) were designed in [ 10 , 11 ] for the catalytic processing of light hydrocarbons into synthesis gas. The catalysts are composed of a high-heat-conducting FeCrAl block covered by θ-Al 2 O 3 and a layer of ceria–zirconia mixed oxide with deposited 2–3 nm sized Pt, Rh, or Ru nanoparticles.…”

“…The catalysts are composed of a high-heat-conducting FeCrAl block covered by θ-Al 2 O 3 and a layer of ceria–zirconia mixed oxide with deposited 2–3 nm sized Pt, Rh, or Ru nanoparticles. Reformates were produced via the reformation of propane steam over the designed catalysts at 600 °C; the reformates contained ~65 vol.% of H 2 , which can be used as a fuel for solid oxide fuel cells [ 11 ]. In addition, the authors studied the catalytic properties of the Rh/Ce 0.75 Zr 0.25 O 2 /Al 2 O 3 /FeCrAl composite catalyst with respect to the conversion of diesel fuel into synthesis gas and concluded that it can be used in fuel cell power generators [ 10 ].…”