Production of hydrogen by ethanol steam reforming on Co/Al2O3 catalysts: Effect of addition of small quantities of noble metals

The catalytic performance of Co/Al2O3 catalysts promoted with small amounts noble metals (Pt, Pd, Ru, Ir) for steam reforming of ethanol (SRE) has been investigated. The catalysts were characterized by the energy dispersive X-ray, X-ray diffraction, BET surface area, X-ray absorption fine structure and temperature reduction programmed techniques. The results showed that the promoting effect of noble metals included a marked decrease of the reduction temperatures of both Co3O4 and cobalt surface species interacting with the support due to the hydrogen spillover effect, leading to a significant increase of the reducibilities of the promoted catalysts. The better catalytic performance for the ethanol steam reforming at 400 degrees C was obtained for the CoRu/Al2O3 catalyst, which presented an effluent gaseous mixture with the highest H, selectivity and the reasonable low CO formation. (C) 2007 Published by Elsevier B.V.

Co catalysts supported on SiO(2) and gamma-Al(2)O(3) applied to ethanol steam reforming: Effect of the solvent used in the catalyst preparation method

Cobalt catalysts were prepared on supports of SiO(2) and gamma-Al(2)O(3) by the impregnation method, using a solution of Co precursor in methanol. The samples were characterized by XRD, TPR, and Raman spectroscopy and tested in ethanol steam reforming. According to the XRD results, impregnation with the methanolic solution led to smaller metal crystallites than with aqueous solution, on the SiO(2) support. On gamma-Al(2)O(3), all the samples exhibited small crystallites, with either solvent, due to a higher Co-support interaction that inhibits the reduction of Co species. The TPR results were consistent with XRD results and the samples supported on gamma-Al(2)O(3) showed a lower degree of reduction. In the steam reforming of ethanol, catalysts supported on SiO(2) and prepared with the methanolic solution showed the best H(2), CO(2) and CO selectivity. Those supported on gamma-Al(2)O(3) showed lower H(2) selectivity. (C) 2011 Elsevier Ltd. All rights reserved.

Cobalt catalysts derived from hydrotalcite-type precursors applied to steam reforming of ethanol

Catalysts derived from Co/Mg/Al hydrotalcite-type precursors modified with La and Ce were characterized by XANES and tested in ethanol steam reforming. The reaction data showed that, with a molar ratio of water: ethanol = 3:1 in the feed, addition of Ce and La favored acetaldehyde production. Increasing the water content (water:ethanol = 5:1) decreased the acetaldehyde formation by favoring the adsorption of water molecules on these samples, enhancing the acetaldehyde conversion. (C) 2011 Elsevier B.V. All rights reserved.

Effects of adding La and Ce to hydrotalcite-type Ni/Mg/Al catalyst precursors on ethanol steam reforming reactions

Catalyst precursors composed of Ni/Mg/Al oxides with added La and Ce were tested in ethanol steam reforming (ESR) reactions. La and Ce were added by anion-exchange. The oxides were characterized by X-ray photoelectron spectroscopy (XPS) and X-ray absorption near-edge structure (XANES) analysis. The catalyst precursors consist of a mixture of oxides, with the nickel in the form of NiO strongly interacting with the support Mg/Al. The XPS analysis showed a lanthanum-support interaction, but no interaction of Ce species with the support. The reaction data obtained with the active catalysts showed that the addition of Ce and La resulted in better H(2) production at 550 degrees C. The CeNi catalyst provided the higher ethanol conversion, with lower acetaldehyde production, possibly clue to a favoring of water adsorption on the weakly interacting clusters of CeO(2) on the surface. (C) 2010 Elsevier B.V. All rights reserved.

Ni catalysts with Mo promoter for methane steam reforming

NiO/Al(2)O(3) catalyst precursors were prepared by simultaneous precipitation, in a Ni:Al molar ratio of 3:1, promoted with Mo oxide (0.05, 0.5, 1.0 and 2.0 wt%). The solids were characterized by adsorption of N(2), XRD, TPR, Raman spectroscopy and XPS, then activated by H(2) reduction and tested for the catalytic activity in methane steam reforming. The characterization results showed the presence of NiO and Ni(2)AlO(4) in the bulk and Ni(2)AlO(4) and/or Ni(2)O(3) and MoO(4)(-2) at the surface of the samples. In the catalytic tests, high stability was observed with a reaction feed of 4:1 steam/methane. However, at a steam/methane ratio of 2: 1, only the catalyst with 0.05% Mo remained stable throughout the 500 min of the test. The addition of Mo to Ni catalysts may have a synergistic effect, probably as a result of electron transfer from the molybdenum to the nickel, increasing the electron density of the catalytic site and hence the catalytic activity. (C) 2009 Elsevier Ltd. All rights reserved.

Ambiguous Artefacts : Solar Collectors in Swedish Contexts. On Processes of Cultural Modification

This is a book about solar collectors and the place of these artefacts in a political energy debate that has aroused strong feelings in Sweden during the last twenty-five years. It is a book about the hopes for a less polluted earth, which solar collectors have come to symbolise, and a book about the ways in which problems in utilising solar energy are culturally perceived. One main aims of this study has been to find out more about the conflicting perceptions of solar collectors as 'saviours of the world' and simultaneously as uninteresting or less credible artefacts that 'may come in the future'. Another main purpose of the study has been to describe and explain those cultural processes of modification that are taking place around solar collectors in active attempts to integrate these into established cultural structures.

Integrated Product Development in Truck Industry - A Case Study on Product Development Processes

This paper presents the result from a case study at Scania on product development processes. The objective with the case study was to gather information on Scania’s product development process (PDP) including the use of CAD and simulation tools, and project work. The objective was also to find any deviations or different interpretations among the employees on the PDP. To gather the information, semi-structured tape-recorded interviews have been used to ensure that individual interpretations from the interviewees could be gathered. Scania uses a defined and structured PDP which facilitates concurrent and cross-functional work. The PDP is implemented and followed to various degrees. The newly employed personnel may have difficulties with communication, both to find and to give information. Although, newly graduated personnel may find it easier to adapt to changes, and also to use a structured process which they have studied at universities. It was also known during the case study that the PDP is a major support for the newly employed personnel, which in turn decreases the time to get into the same working process as the more experienced personnel. Employees with decades of experience know the right sources from which to both give and gather information. Also, the terminology and definitions in the product development process may not be used as intended. This makes it difficult for other project members or teams who need to interpret the information received. At the same time, the routines among the more experienced personnel, which have been set-up throughout the years, make them more inflexible in adapting changes. The findings in the case study as well as challenges with implementing the PDP are known to Scania and are a part of the continuing work with improvement.

Processes of feelings in a society with a violent past : A qualitative study of the communication for Societal healing in the Truth Commissions in East Timor, Sri Lanka and Ghana between 2002-2011

The research investigates in what extent and how communication for meeting feelings is provided in Truth Commission work. It examines if and in what way feelings are addressed in the communication officially published by the Truth Commissions in East Timor, Ghana and Sri Lanka, occurring between 2002-2011. The research is also looking at the healing processes in a time perspective to find out if there is a communication for Societal healing to be continued in a longer term. My conclusion is that two cases of three in my research, the TRCs in Ghana and East Timor, have communication clearly directed to meet feelings caused by the war. One of the three cases (East Timor) has a communication with a clear ambition to heal over a longer period, to continue after the existence of the Truth Commission. The research suggests that communication with a clear ambition to reach out widely in the society, a communication directed to meet and process feelings over a longer period, can make Societal healing more effective. It also concludes that, in the future, Societal healing, as a field in conflict resolution, will be more based on representational media than today, provided through web communication.

Processes and variations in language economisation

This article analyses the processes of reducing language in textchats produced by non-native speakers of English. We propose that forms are reduced because of their high frequency and because of the discourse context. A wide variety of processes are attested in the literature, and we find different forms of clippings in our data, including mixtures of different clippings, homophone respellings, phonetic respellings including informal oral forms, initialisms (but no acronyms), and mixtures of clipping together with homophone and phonetic respellings. Clippings were the most frequent process (especially back-clippings and initialisms), followed by homophone respellings. There were different ways of metalinguistically marking reduction, but capitalisation was by far the most frequent. There is much individual variation in the frequencies of the different processes, although most were within normal distribution. The fact that nonnative speakers seem to generally follow reduction patterns of native speakers suggests that reduction is a universal process.

Using Normative Markov Decision Processes for Evaluating Electronic Contracts: A Case Study in a Simulated Aerospace Aftermarket

Before signing electronic contracts, a rational agent should estimate the expected utilities of these contracts and calculate the violation risks related to them. In order to perform such pre-signing procedures, this agent has to be capable of computing a policy taking into account the norms and sanctions in the contracts. In relation to this, the contribution of this work is threefold. First, we present the Normative Markov Decision Process, an extension of the Markov Decision Process for explicitly representing norms. In order to illustrate the usage of our framework, we model an example in a simulated aerospace aftermarket. Second, we specify an algorithm for identifying the states of the process which characterize the violation of norms. Finally, we show how to compute policies with our framework and how to calculate the risk of violating the norms in the contracts by adopting a particular policy.