The Pechini synthesis was used to prepare nickel aluminate catalysts with the compositions NiAl 4 O 7 , NiAl 2 O 4 , and Ni 2 Al 2 O 5. The samples are characterized by N 2 physisorption, temperature programmed reduction (TPR), temperature programmed oxidation (TPO), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), and X-ray absorption spectroscopy (XAS). Characterization results indicate unique structural properties and excellent regeneration potential of nickel aluminates. Prepared samples are tested when unreduced and reduced prior to reaction for methane dry reforming and methane steam reforming reactivity. NiAl 2 O 4 in the reduced and unreduced state as well as NiAl 4 O 7 in the reduced state are active and stable for methane dry reforming due to the presence of four-fold coordinated oxidized nickel. The limited amount of metallic nickel in these samples minimizes carbon deposition. On the other hand, the presence of metallic nickel is required for methane steam reforming. Ni 2 Al 2 O 5 in the reduced and unreduced state and NiAl 2 O 4 in the reduced state are found to be active for methane steam reforming due to the presence of sufficiently small nickel nanoparticles that catalyze the reaction without accumulating carbonaceous deposits.

Carbide-derived carbons with embedded Fe nanoparticles are synthesized by partial chlorination of iron carbide at 600 o C. Interestingly, the residual Fe studied by X-ray absorption near edge spectroscopy, scanning electron microscopy, and transmission electron microscopy show the extraction process does not follow a layer-by-layer extraction process, as proposed in the literature for the chlorination of other carbides. Instead, a large percentage of iron carbide converts to iron (II) and iron (III) chloride nanoparticles, which remain trapped within the resulting nanoporous carbon framework. Further reductive treatment can be used to produce dispersed Fe nanoparticles with an average particle diameter approaching 10nm.

Titanium carbide-derived carbon with residual metal is synthesized by partial chlorination at 500 °C. This partial metal removal in the carbide creates vacancies, about which the carbon reorganizes to form an amorphous, porous carbon structure. To understand the titanium removal process on a bulk scale, three reactor designs were tested: (1) a flow-over horizontal-bed reactor, (2) a vertical flow-through packed-bed reactor, and (3) a fluidized-bed reactor. These reactors were chosen to investigate how various Cl 2 flow patterns impact the etching uniformity on individual TiC-CDC particles. Both the horizontal-and packed-bed reactors lost approximately

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