Neutron diffraction studies of nickel-containing perovskite oxide catalysts exposed to autothermal reforming environments.

Journal Article · Tue Oct 27 00:00:00 EDT 2009 · Chem. Mater.

DOI:https://doi.org/10.1021/cm901095v· OSTI ID:986291

Mawdsley, J R; Vaughey, J T; Krause, T R

Six nickel-containing perovskite oxides (La{sub 1-x}Sr{sub x})M{sub 0.9}Ni{sub 0.1}O{sub 3{+-}{delta}}, where x = 0 or 0.2 and M = Cr, Fe, or Mn were used to catalyze the autothermal reforming of isooctane (C{sub 8}H{sub 18}) into a hydrogen-rich gas during short-term tests at 700 C. To determine the phase stability of the samples in the reducing environment of the reforming reactor, characterization studies of the as-prepared and tested perovskite samples were conducted using powder X-ray diffraction, powder neutron diffraction, transmission electron microscopy, and scanning electron microscopy. We determined that the reducing conditions of the microreactor caused metallic nickel to form in all six compositions. However, the extent of the nickel loss from the perovskite lattices varied: the chromium-containing compositions lost the least nickel, compared to the manganese- and iron-containing compositions, and the strontium-free compositions lost more nickel than their strontium-containing analogs. Five of the six perovskite compositions tested showed no breakdown of the perovskite lattice despite the loss of nickel from the B-sites, producing only the third example of a B-cation-deficient, 3d transition-metal-containing perovskite.

• Research Organization: Argonne National Lab. (ANL), Argonne, IL (United States)
• Sponsoring Organization: EE; USDOE Office of Science (SC)
• DOE Contract Number: DE-AC02-06CH11357
• OSTI ID: 986291
• Report Number(s): ANL/CSE/JA-64095; TRN: US201017%%50
• Journal Information: Chem. Mater., Vol. 21, Issue 20 ; Oct. 27, 2009
• Country of Publication: United States
• Language: ENGLISH

Related Subjects

37 INORGANIC
ORGANIC
PHYSICAL AND ANALYTICAL CHEMISTRY
CATALYSTS
MANGANESE OXIDES
NEUTRON DIFFRACTION
NICKEL OXIDES
PEROVSKITE
PHASE STABILITY
LANTHANUM OXIDES
STRONTIUM OXIDES
CHROMIUM OXIDES
IRON OXIDES
ALKANES
AUTOTHERMAL REFORMER PROCESSES
X-RAY DIFFRACTION
SCANNING ELECTRON MICROSCOPY
TRANSMISSION ELECTRON MICROSCOPY