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Activated carbons from Spanish coals have been prepared by chemical activation with alkali and alkaline-earth hydroxides. The paper analyzes the following aspects: presence of water during pyrolysis, extension of the impregnation and drying processes, activating agent, temperature and time of pyrolysis, activating agent/coal ratio, coal rank, and mineral matter content. KOH and NaOH activation provides very successful results in which N 2 apparent surface areas of 2500 m 2 /g are obtained; contrarily, Ca(OH) 2 produces a small porosity development. A pyrolysis temperature of 700 °C yields activated carbons with a wider pore size distribution than those prepared at 500 °C. The pyrolysis time does not affect the microporosity development but an important reduction in the ash content is observed when the time is increased. The use of an activating agent/coal ratio of 2/1 compared to 1/1 has favorable effects: (i) a decrease in the ash content and (ii) a wider pore size distribution. The addition of a drying step before pyrolysis greatly increases the nitrogen surface area and decreases the ash content. Porosity development depends on the coal rank. Low rank coals yield activated carbons with wider pore size distributions. The chemical activation process presents the great advantage, compared to physical activation, of removing the inherent mineral matter of the coal. Activated carbons obtained by chemical activation exhibit much lower ash content than the corresponding original coals. Ash reduction, depending on the coal used, could be very noticeable; the highest reduction observed corresponds to coal UA10 (11.3% ash) that, after NaOH activation, results in an activated carbon with only 0.5% ash content.

Please cite this article as: J. Giménez-Mañogil, A. Bueno-López, A. García-García, Preparation, characterisation and testing of CuO/Ce 0.8 Zr 0.2 O 2 catalysts for NO oxidation to NO 2 and mild temperature diesel soot combustion., Applied Catalysis B, Environmental (2014), http://dx.doi.org/10. 1016/j.apcatb.2014.01.018 This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain. AbstractCuO/ceria-zirconia catalysts have been prepared, deeply characterised (N 2 adsorption-desorption isotherms at -196°C, XRD, Raman spectroscopy, XPS, TEM and H 2 -TPR) and tested for NO oxidation to NO 2 in TPR conditions, and for soot combustion at mild temperature (400ºC) in a NOx/O 2 stream. The behaviour has been compared to that of a reference Pt/alumina commercial catalyst. The ceria-zirconia support was prepared by the co-precipitation method, and different amounts of copper (0.5, 1, 2, 4 and 6 wt%) were loaded by incipient wetness impregnation.The results revealed that copper is well-dispersed onto the ceria-zirconia support for the catalysts with low copper loading and CuO particles were only identified by XRD in samples with 4 and 6% of copper. A very low loading of copper increases significantly the activity for the NO oxidation to NO 2 with regard to the ceria-zirconia support and an optimum was found for a 4%CuO/ceria-zirconia composition, showing a very high activity (54% at 348ºC). The soot combustion rate at 400ºC obtained with the 2%CuO/ceria-zirconia catalyst is slightly lower to that of 1%Pt/alumina in terms of mass of catalyst but higher in terms of price of catalyst.

Abstract:12 13 A Ce0.5Pr0.5O2 mixed oxide has been prepared with the highest surface area and smallest 14 particle size ever reported (125 m 2 /g and 7 nm respectively), also being the most active

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