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A unique 1D nanostructure of Pt@CeO 2 −BDC was prepared from Pt@CeBDC MOF. The Pt@CeO 2 −BDC was rich in oxygen vacancies (i.e., XPS O β /(O α + O β ) = 39.4%), and on the catalyst, the 2 nm Pt clusters were uniformly deposited on the 1D mesoporous polycrystalline CeO 2 . Toluene oxidation was conducted in a spectroscopic operando Raman−online FTIR reactor to elucidate the reaction mechanism and establish the structure−activity relationship. The reaction proceeds as follows: (I) adsorption of toluene as benzoate intermediates on Pt@CeO 2 −BDC at low temperature by reaction with surface peroxide species; (II) reaction activation and ring-opening involving lattice oxygen with a concomitant change in defect densities indicative of surface rearrangement; (III) complete oxidation to CO 2 and H 2 O by lattice oxygen and reoxidation of the reduced ceria with consumption of adsorbed oxygen species. The Pt clusters, which mainly exist as Pt 2+ with minor amounts of Pt 0 and Pt 4+ on the surface, facilitated the adsorption and reaction activation. The Pt-CeO 2 interface generates reduced ceria sites forming nearby adsorbed peroxide at low temperature that oxidize toluene into benzoate species by a Langmuir−Hinshelwood mechanism. As the reaction temperature increases, the role of lattice oxygen becomes important, producing CO 2 and H 2 O mainly by the Mars-van Krevelen mechanism.

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a b s t r a c tHydrotalcite-like precursors have been synthesized in order to study the influence of lanthanum on the structure and the properties of the precursors, as well as on the catalytic activity and stability of their derived catalyst on biogas reforming. From XRD, and TPO characterization, we confirmed that hydrotalcite-like precursors where obtained. After calcination at 750 • C, Mg(Ni,Al)O solid solution was detected. High surface areas have been obtained finding the highest surface area on the catalyst without lanthanum. TPR experiments were performed in order to study the reducibility of the catalysts. One reduction peak was found in the catalyst without lanthanum while two peaks were observed in the catalysts with lanthanum. A reduction peak at 900 • C was observed over the sample without Ni and La. Catalytic tests, at 700 • C with a feed of CH 4 :CO 2 1:1, were performed after appropriate reduction during 50 h. While a decrease on catalytic activity was observed with the addition and the increase of La content, an enhancement in the stability was observed. No sign of deactivation of the catalyst and no carbon deposition were found on the catalysts doped with lanthanum.

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Extruded catalysts show efficient conversion of sunflower oil into biodiesel. The reaction achieved practically total conversion using 35%K 2 CO 3 /65%-Al 2 O 3 at 2h. After transesterification high-quality biodiesel was attained according ASTM/EN specifications. Highlights (for review)

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