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The transition toward a "Hydrogen Economy" could ensure significant advantages in terms of energetic efficiency and environmental impact, with reduced production of greenhouse gases. In the near term, considering the actual lack of infrastructure for H2 storage and distribution, equipment operating with FCs fed with H2 or H2-rich gases, produced by reforming of available fossil (Natural Gas, LPG, Diesel, etc..) and renewable (biogas, bioethanol) fuels, represent a valid and interesting alternative to actual energy generation systems. Even if the reforming technologies are mature, especially SR for hydrogen production on a large scale, more efforts are required for process intensification developing compact systems for small-scale distributed hydrogen production (50-1500 kg/day). Central issues of reforming processes for small-scale application are the development of efficient, stable and low-cost catalysts coupled with the realization of compact and lightweight, fuel processor. In this work, the performances of structured catalysts, based on Rh (1.5wt.%), supported on CeO2, coated on cordierite monoliths (400 cpsi, diameter 1 cm, length 1.5 cm) and alumina foams (20, 30, 40 PPI) were investigated and compared under Steam Reforming (SR) and Oxy Stream Reforming (OSR) of methane (CH4), n-dodecane (n-C12H26) and biogas (CH4=60%, CO2=40%). The structured supports were lined with a novel procedure combining the Solution Combustion Synthesis with the Impregnation technique. All prepared catalysts were characterized by XRD, TEM, SEM and chemisorption analyses. Both monolith and foam catalysts have shown comparable characteristics in terms of uniform thin coating (thickness between 20-30 ?m), high mechanical strength (negligible weight loss ? 0.4% on total weight of the sample after ultrasonic treatment); a low-pressure drop of the monolith respect the foam was observed. In general both foam and monolith samples have shown good catalytic performances, also at high flow rates, in terms of high fuel conversion (CH4Methane = 99-90%, CH4biogas = 99-98%, n-C12H26 = 99% for SR process and CH4Methane = 99-98%, CH4biogas = 99-96%, n-C12H26 = 99% for OSR process) and hydrogen concentration (H2methane= 76-74, H2biogas = 64-62%, H2n-C12H26 = 72-70% in dry and nitrogen-free basis for SR process and H2methane = 69-68%, H2biogas = 59-58%, H2n-C12H26 = 64-60%, in dry basis and nitrogen free for OSR process). The obtained results represent a promising advance in the process intensification of fuel reforming technology: high performances at high space velocity, together with relatively low-cost catalysts, involve a more compact, lightweight and less expensive fuel processors.

The transition toward a "Hydrogen Economy" could ensure significant advantages in terms of energetic efficiency and environmental impact, with reduced production of greenhouse gases. In the near term, considering the actual lack of infrastructure for H2 storage and distribution, equipments operating with FCs fed with H2 or H2-rich gases produced by reforming of available fossil (Natural Gas, LPG, Diesel, etc..) and renewable (biogas, bioethanol) fuels represent a valid and interesting alternative to actual energy generation systems [1,2]. Additionally, large-scale central production will depend on market volumes to evolve in order to compensate for the capital expenditures of building up capacity. Thus, distributed production of hydrogen/syngas via smaller reformer, integrated with different fuel cell systems (SOFC, PEM), is viewed as an attractive near option for stationary. Combined Heat and Power System (CHPS). Moreover, the reforming of fossil fuels could represent a practical option to create H2 filling stations realized with on-site fuel processor (FP) units fed with distribuited fuels already present on the road [3]. The key requirements for a fuel processor include rapid start-up, good dynamic-response to follow the change in hydrogen demand, high fuel conversion, small size and weight, simple design (construction and operation), stable performance for repeated start-up and shut-down cycles, maximum thermal integration, low cost and maintenance, high reliability and safety. In addition, the design of robust, low cost, highly performing and relatively fuelflexible catalysts is also required. In this regards, structured reactors, such as microchannels, ceramic or metallic monoliths and foams, show a number of advantages, like, compactness, high power densities, high mass specific powers, low catalyst request, lower pressure drop and improved heat and mass transfer, compared to conventional technology such as packet beds [4]. In this work, the performances of structured catalysts, based on 1.5wt%Rh/CeO2 coated on cordierite monoliths (400 cpsi, diameter 1 cm, length 1.5 cm) and alumina foams (20, 30, 40 ppi, diameter 1 cm, length 1.5 cm) were investigated and compared towards Steam Reforming (SR) and Oxy Steam Reforming (OSR) of different fuels (CH4, Biogas, n-dodecane). The structured supports were lined by combining the Solution Combustion Synthesis (SCS) for the deposition of ceria oxide, with the Wet Impregnation Technique (WIT) for the loading of active metal. The deposition process was repeated several times until reaching the desired and equal amount (? 0.180mg) of catalytic layer over all the supports [5]. The final structured catalysts, showed in Fig. 1, were characterized by SEM, EDX-mapping, TEM and XRD techniques; in addition, Rh/CeO2 catalyst in powder form was also prepared by the same procedure and characterized by XRD, TPR and CO chemisorption analysis. Pressure drop and catalytic layer loss tests have been evaluated. Both monolith and foam catalysts have shown comparable results in terms of uniform thin coating (thickness between 20-30 ?m), high mechanical strength (negligible weight loss ? 0.4% on total weight of the sample after ultrasonic treatment) with low pressure drop of the monolith respect the foam. The different reforming experiments were conducted in a fixed-bed quartz reactor (?i = 1 cm) at atmospheric pressure. The overall operating conditions are summarized in table 1. A first series of tests were carried out only with monolith catalysts to identify the optimum conditions in terms of S/C for SR, S/C and O/C for OSR for each fuel at fixed intermediate WSV and temperature. A second series of tests were carried out to compare the catalytic performance of foam and monolith catalysts varying the temperature and the WSV.

As a young discipline, Computer Science does not rely on longly tested didactic procedures. This allows the experimentation of innovative teaching methods at schools, especially in early childhood education. Our approach is based on the idea that abstracts notions should be gained as the final result of a learning path made of concrete and touchable steps. To illustrate our methodology, we present some of the teaching projects we proposed.