Browsing by Keyword "Pollution"

Now showing 1 - 20 of 60
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    Application of ecological risk assessment based on a novel TRIAD-tiered approach to contaminated soil surrounding a closed non-sealed landfill
    (2015-05-01) Gutiérrez, Laura; Garbisu, Carlos; Ciprián, Estela; Becerril, José M.; Soto, Manu; Etxebarria, Javier; Madariaga, Juan M.; Antigüedad, Iñaki; Epelde, Lur; Tecnalia Research & Innovation; Mercado
    The Ecological Risk Assessment (ERA) is a reliable tool for communicating risk to decision makers in a comprehensive and scientific evidence-based way. In this work, a site-specific ERA methodology based on the TRIAD approach was applied to contaminated soil surrounding a closed non-sealed landfill, as a case study to implement and validate such ERA methodology in the Basque Country (northern Spain). Initially, the procedure consisted of the application of a Parameter Selection Module aimed at selecting the most suitable parameters for the specific characteristics of the landfill contaminated soil, taking into consideration the envisioned land use, intended ecosystem services and nature of contaminants. Afterwards, the selected parameters were determined in soil samples collected from two sampling points located downstream of the abovementioned landfill. The results from these tests were normalized to make them comparable and integrable in a risk index. Then, risk assessment criteria were developed and applied to the two landfill contaminated soil samples. Although the lack of a proper control soil was evidenced, a natural land use was approved by the ERA (at Tier 2) for the two landfill contaminated soils. However, the existence of a potential future risk resulting from a hypothetical soil acidification must be considered.
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    Assessment of nanoparticles release into the environment during drilling of carbon nanotubes/epoxy and carbon nanofibres/epoxy nanocomposites
    (2017-10-15) Starost, Kristof; Frijns, Evelien; Van Laer, Jo; Faisal, Nadimul; Egizabal, Ainhoa; Elizetxea, Cristina; Blazquez, Maria; Nelissen, Inge; Njuguna, James; Elizextea, Cristina; Biomateriales; POLIMEROS
    The risk assessment, exposure and understanding of the release of embedded carbon nanotubes (CNTs) and carbon nanofibers (CNFs) from commercial high performance composites during machining processes are yet to be fully evaluated and quantified. In this study, CNTs and CNFs were dispersed in epoxy matrix through calendaring process to form nanocomposites. The automated drilling was carried out in a specially designed drilling chamber that allowed elimination of background noise from the measurements. Emission measurements were taken using condensed particle counter (CPC), scanning mobility particle sizer (SMPS) and DMS50 Fast Particulate Size Spectrometer. In comparison to the neat epoxy, the study results revealed that the nano-filled samples produced an increase of 102% and 227% for the EP/CNF and EP/CNT sample respectively in average particle number concentration emission. The particle mass concentration indicated that the EP/CNT and EP/CNF samples released demands a vital new perspective on CNTs and CNFs embedded within nanocomposite materials to be considered and evaluated for occupational exposure assessment. Importantly, the increased concentration observed at 10 nm aerosol particle sizes measurements strongly suggest that there are independent CNTs being released at this range.
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    Chemicals from biomass: Synthesis of lactic acid by alkaline hydrothermal conversion of sorbitol
    (2011-06) Ramírez-López, Camilo A.; Ochoa-Gómez, José R.; Gil-Río, Silvia; Gómez-Jiménez-Aberasturi, Olga; Torrecilla-Soria, Jesús; Tecnalia Research & Innovation; Laboratorio Químico; BIOECONOMÍA Y CO2; SG
    BACKGROUND: Currently, the 'green chemistry' philosophy is being increasingly adopted by the chemical industry and, therefore, new production procedures of valuable chemicals from biomass-derived raw materials are being sought. In this work, the synthesis of lactic acid from sorbitol under alkaline hydrothermal conditions is investigated by analyzing the influence on conversions and yields of temperature, NaOH/sorbitol molar ratio (MR), initial sorbitol concentration (SC) and reaction time. RESULTS: A 100% sorbitol conversion and a maximum 39.5% yield of lactic acid on a carbon basis are obtained at 280 °C, 50 min, 1.0 mol L-1 SC and 2.0 MR. Glyceraldehyde was the only identified intermediate while formic acid, acrylic acid, acetic acid, oxalic acid and sodium carbonate were identified as over-oxidation products, all of them in very low yields with the exception of formic acid (16% yield at a MR of 4 and 280 °C). Several plausible conversion routes of sorbitol involving dehydrations, keto-enol tautomerisms, reverse aldol condensations, aldol condensations, Cannizzaro reactions and oxidations are proposed. CONCLUSIONS: Considering the high number of parallel conversion routes as a consequence of high functionality of sorbitol, the 39.5% lactic acid yield obtained is a good result. Total carbon mass in all identified products only justifies, at most, 50% of that in sorbitol due to the coexistence of several conversion routes resulting in a large number of products other than lactic acid.
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    Compact fixturing based on magneto-rheological fluids for aeronautic stringers milling
    (2010) de la O Rodríguez, M.; Collado, V.; Böse, H.; Gerlach, T.; Würtz, T.; Holz, B.; May, C.; Thoelen, J.; Porras, E.; Marcos, J.; Ionescu, M.; ROBOTICA_AUTOMA; MAQUINAS
    The paper explains the compact fixturing based on magneto-rheological (MR) fluids that have been designed and validated for aeronautic stringers milling. The MR fluid based tooling developed is flexible and reconfigurable as it can be adapted to different profile's lengths and sections and it is able to fix compliant workpieces without reference faces as the MR fluid adapts to the outer shape of each profile. The MR fluid based tooling is suitable to hold non-magnetic materials such as aluminum and also materials that do not admit high clamping forces, such as titanium, because they will appear as deformation after machining due to the memory effect of titanium. The MR fluid based tooling has been tested in a machine environment under real machining conditions and promising results have been obtained.
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    A comparative study on the performance of ventilated brake discs manufactured in different advanced materials
    (2001) Goñi, J.; Mitxelena, I.; Rubio, A.; Coleto, J.; Terrón, A.; García, A.; Sánchez, J.; Centros PRE-FUSION TECNALIA - (FORMER); Tecnalia Research & Innovation; Mercado
    Two different aluminium alloy materials have been used to produce ventilated brake discs, on one hand, AS17G0.6 hypereutectic alloy and on the other hand, AS7G0.6 reinforced with 20% in wt. of SiC particles. The casting production technique used has been Low Pressure Casting (LPC) and some of the brake discs have been heat treated using a T6 treatment. Once the ventilated brake discs were produced and machined, they were tested in a dynamometer in order to compare the performance under service conditions of the aluminum alloy and grey cast iron (GCI) discs currently used in the market.
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    Competitive removal of pharmaceuticals from environmental waters by adsorption and photocatalytic degradation
    (2014-08-01) Rioja, N.; Benguria, P.; Peñas, F. J.; Zorita, S.; MATERIALES PARA CONDICIONES EXTREMAS; ADAPTACIÓN AL CAMBIO CLIMÁTICO
    This work explores the competitive removal of pharmaceuticals from synthetic and environmental waters by combined adsorption-photolysis treatment. Five drugs usually present in waterways have been used as target compounds, some are pseudo-persistent pollutants (carbamazepine, clofibric acid, and sulfamethoxazole) and others are largely consumed (diclofenac and ibuprofen). The effect of the light source on adsorption of drugs onto activated carbons followed by photolysis with TiO2 was assessed, being UV-C light the most effective for drug removal in both deionized water and river water. Different composites prepared from titania nanoparticles and powdered activated carbons were tested in several combined adsorption-photocatalysis assays. The composites prepared by calcination at 400 °C exhibited much better performance than those synthesized at 500 °C, being the C400 composite the most effective one. Furthermore, some synthetic waters containing dissolved species and environmental waters were used to investigate the effect of the aqueous matrix on each drug removal. In general, photocatalyst deactivation was found in synthetic and environmental waters. This was particularly evident in the experiments performed with bicarbonate ions as well as with wastewater effluent. In contrast, tests conducted in seawater showed adsorption and photocatalytic degradation yields comparable to those obtained in deionized water. Considering the peculiarities of substrate competition in each aqueous matrix, the combined adsorption-photolysis treatment generally increased the overall elimination of drugs in water.
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    Corrigendum to “Data driven model for heat load prediction in buildings connected to District Heating by using smart heat meters” [Energy 239, Part D, 2022, 122318] (Energy (2022) 239(PD), (S0360544221025664), (10.1016/j.energy.2021.122318))
    (2022-08-15) Lumbreras, Mikel; Garay-Martinez, Roberto; Arregi, Beñat; Martin-Escudero, Koldobika; Diarce, Gonzalo; Raud, Margus; Hagu, Indrek; Tecnalia Research & Innovation; EDIFICACIÓN DE ENERGÍA POSITIVA
    The authors regret to inform that, even after careful revisions in all stages of the manuscript, a relevant typographic error has been found in the published version of the paper. The error is found in the definition of the so-called Q-algorithm in Eq. (1), where the selection among two formulae is performed based on the actual heat load (Q) compared to a reference heat load (QREF). The correct formulation for equation can be found in Eq. (1) below. [Formula presented] The authors would like to apologise for any inconvenience caused.
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    Data driven model for heat load prediction in buildings connected to District Heating by using smart heat meters
    (2022-01-15) Lumbreras, Mikel; Garay-Martinez, Roberto; Arregi, Beñat; Martin-Escudero, Koldobika; Diarce, Gonzalo; Raud, Margus; Hagu, Indrek; Tecnalia Research & Innovation; EDIFICACIÓN DE ENERGÍA POSITIVA
    An accurate characterization and prediction of heat loads in buildings connected to a District Heating (DH) network is crucial for the effective operation of these systems. The high variability of the heat production process of DH networks with low supply temperatures and derived from the incorporation of different heat sources increases the need for heat demand prediction models. This paper presents a novel data-driven model for the characterization and prediction of heating demand in buildings connected to a DH network. This model is built on the so-called Q-algorithm and fed with real data from 42 smart energy meters located in 42 buildings connected to the DH in Tartu (Estonia). These meters deliver heat consumption data with a 1-h frequency. Heat load profiles are analysed, and a model based on supervised clustering methods in combination with multiple variable regression is proposed. The model makes use of four climatic variables, including outdoor ambient temperature, global solar radiation and wind speed and direction, combined with time factors and data from smart meters. The model is designed for deployment over large sets of the building stock, and thus aims to forecast heat load regardless of the construction characteristics or final use of the building. The low computational cost required by this algorithm enables its integration into machines with no special requirements due to the equations governing the model. The data-driven model is evaluated both statistically and from an engineering or energetic point of view. R2 values from 0.70 to 0.99 are obtained for daily data resolution and R2 values up to 0.95 for hourly data resolution. Hourly results are very promising for more than 90% of the buildings under study.
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    Design Features of an Innovative Synchronous Reluctance Machine for Battery Electric Vehicles Applications
    (2016) Gragger, Johannes; Zanon, Alessandro; De Gennaro, Michele; Juergens, Jonathan; Fricassè, Antonio; Marengo, Luca; Olavarria, Igor; Kinder, Jutta; Tecnalia Research & Innovation
    The widespread of hybrid and battery electric vehicles is vital for the future of low-carbon mobility. In this context the delivery of affordable and efficient electric motor technologies together with high energy density storage devices are key aspects to enable the mass market take-off of electrified vehicles. The objective of this paper is to provide the scientific community with the results and design features of an innovative and rare-earth free electric motor technology based on the synchronous reluctance machine concept. This technology is capable to provide sufficient power density and higher driving cycle energy efficiency compared to the current state-of-the-art rare-earth permanent magnet synchronous machines used for automotive applications. The motor is designed to be integrated within a hatchback rear driving axle vehicle, achieving the maximum energy efficiency in urban operational conditions. The paper shortly presents the motor design objectives, to then focus on the main design steps undertaken, i.e. stator winding design, electromagnetic and mechanical design, power electronics hardware design and integrated thermal design. The final motor design and its preliminary performances are presented, showing a maximum torque performance of 133 Nm at 3,700 rpm and a maximum power of 56.7 kW at 4,900 rpm, with peak efficiency above 96% around 4,000±500 rpm and 50±20 Nm, decreasing to 93-94% by including the inverter efficiency (i.e. system efficiency). The proposed motor design constitutes a step ahead in the development of a market-ready permanent magnet assisted synchronous reluctance machine technology for automotive applications, potentially enabling the developed solutions to be successfully implemented in the next generation of electric motors for hybrid and electric vehicles.
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    Detection of non-technical losses in smart meter data based on load curve profiling and time series analysis
    (2017) Villar-Rodriguez, Esther; Del Ser, Javier; Oregi, Izaskun; Bilbao, Miren Nekane; Gil-Lopez, Sergio; Quantum; IA
    The advent and progressive deployment of the so-called Smart Grid has unleashed a profitable portfolio of new possibilities for an efficient management of the low-voltage distribution network supported by the introduction of information and communication technologies to exploit its digitalization. Among all such possibilities this work focuses on the detection of anomalous energy consumption traces: disregarding whether they are due to malfunctioning metering equipment or fraudulent purposes, strong efforts are invested by utilities to detect such outlying events and address them to optimize the power distribution and avoid significant income costs. In this context this manuscript introduce a novel algorithmic approach for the identification of consumption outliers in Smart Grids that relies on concepts from probabilistic data mining and time series analysis. A key ingredient of the proposed technique is its ability to accommodate time irregularities – shifts and warps – in the consumption habits of the user by concentrating on the shape of the consumption rather than on its temporal properties. Simulation results over real data from a Spanish utility are presented and discussed, from where it is concluded that the proposed approach excels at detecting different outlier cases emulated on the aforementioned consumption traces.
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    Development of a biocidal treatment regime to inhibit biological growths on cultural heritage: BIODAM
    (2008-12) Young, M. E.; Alakomi, H. L.; Fortune, I.; Gorbushina, A. A.; Krumbein, W. E.; Maxwell, I.; McCullagh, C.; Robertson, P.; Saarela, M.; Valero, J.; Vendrell, M.; Dirección General
    Existing chemical treatments to prevent biological damage to monuments often involve considerable amounts of potentially dangerous and even poisonous biocides. The scientific approach described in this paper aims at a drastic reduction in the concentration of biocide applications by a polyphasic approach of biocides combined with cell permeabilisers, polysaccharide and pigment inhibitors and a photodynamic treatment. A variety of potential agents were screened to determine the most effective combination. Promising compounds were tested under laboratory conditions with cultures of rock deteriorating bacteria, algae, cyanobacteria and fungi. A subsequent field trial involved two sandstone types with natural biofilms. These were treated with multiple combinations of chemicals and exposed to three different climatic conditions. Although treatments proved successful in the laboratory, field trials were inconclusive and further testing will be required to determine the most effective treatment regime. While the most effective combination of chemicals and their application methodology is still being optimised, results to date indicate that this is a promising and effective treatment for the control of a wide variety of potentially damaging organisms colonising stone substrates.
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    Development of light-weight multifunctional structures
    (2007) Gottero, Marco; Poidomani, Gaetano; Tavera, Salvatore; Sacchi, Enrico; Genbeltzu, Garbiñe Atxaga; EXTREMAT
    Today, in several industrial fields, the integration of functions is a key technology to enhance the efficiency of components in terms of performance to mass/volume/cost/ratio. Concerning the space industry, in the last few years the trend in spacecraft design has been towards smaller, light-weight and higher performance satellites with sophisticated payloads and instrumentation. Increasing power density figures are the common feature of such systems, constituting a challenging task for the Thermal Control System. The traditional mechanical and thermal design concepts are evidencing their limits with reference to such an emerging scenario. A promising solution consists in designing structural elements of a spacecraft that can integrate multiple functions: the capability of realizing a high level of integration of the different subsystems (typically structural strength, thermal control, electronics and shielding) into a multifunctional structure seems to represent an enabling technology in order to respond to the growing demands of present and future space missions. A research program on the development of lightweight high-performance Multifunctional Structures (MFS) has been financed by the European Community under the MULFUN - Multifunctional Structures project. MULFUN is a STRP of the Sixth Framework Programme, carried out by an international team, coordinated by the Spanish Inasmet. Within the consortium, Thales Alenia Space Italia (TAS-I) is mainly in charge of thermal control aspects and thermo-mechanical design. The MFS concept is based on an efficient use of advanced composite materials and components, on disruptive solutions for integrated design, dedicated modeling and simulation tools so as advanced assembly/manufacturing approaches. Based on a deep investigation of the involved concepts and technological needs, the aim of the MULFUN project is the design, the manufacturing and testing of four MFS demonstration breadboards. The first two breadboards are devoted to the integration of thermal control and electrical functions into a unique high-performance structure. Results from this activity are reported in the paper, with emphasis on thermal aspects.
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    Direct route from ethanol to pure hydrogen through autothermal reforming in a membrane reactor: Experimental demonstration, reactor modelling and design: Experimental demonstration, reactor modelling and design
    (2018-01-15) Spallina, V.; Matturro, G.; Ruocco, C.; Meloni, E.; Palma, V.; Fernández-Gesalaga, E.; Melendez, J.; Pacheco Tanaka, David A.; Viviente Sole, J.L.; van Sint Annaland, M.; Gallucci, F.; Tecnalia Research & Innovation; TECNOLOGÍAS DE HIDRÓGENO; TECNOLOGÍA DE MEMBRANAS E INTENSIFICACIÓN DE PROCESOS
    This work reports the integration of thin (∼3–4 μm thick) Pd-based membranes for H2 separation in a fluidized bed catalytic reactor for ethanol auto-thermal reforming. The performance of a fluidized bed membrane reactor has been investigated from an experimental and numerical point of view. The demonstration of the technology has been carried out over 50 h under reactive conditions using 5 thin Pd-based alumina-supported membranes and a 3 wt%Pt-10 wt%Ni catalyst deposited on a mixed CeO2/SiO2 support. The results have confirmed the feasibility of the concept, in particular the capacity to reach a hydrogen recovery factor up to 70%, while the operation at different fluidization regimes, oxygen-to-ethanol and steam-to-ethanol ratios, feed pressures and reactor temperatures have been studied. The most critical part of the system is the sealing of the membranes, where most of the gas leakage was detected. A fluidized bed membrane reactor model for ethanol reforming has been developed and validated with the obtained experimental results. The model has been subsequently used to design a small reactor unit for domestic use, showing that 0.45 m2 membrane area is needed to produce the amount of H2 required for a 5 kWe PEM fuel-cell based micro-CHP system.
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    Do long lived seabirds reduce the negative effects of acute pollution on adult survival by skipping breeding? A study with European storm petrels (Hydrobates pelagicus) during the "Prestige" oil-spill
    (2011-01) Zabala, Jabi; Zuberogoitia, Iñigo; Martínez-Climent, Jose Antonio; Etxezarreta, Jon; ADAPTACIÓN AL CAMBIO CLIMÁTICO
    We estimated the survival probability of breeding European storm petrels before, during and after a severe oil-spill. We hypothesized that petrels might have deserted the breeding colony to maximize their own survival probability and we expected no major change on adult survival probabilities as a consequence of the spill. We used an information-theoretical approach and multi-model inference to assess the strength of the evidence in favour of different hypotheses. Evidence contained in the data clearly supported the non-effect of the spill on adult survival hypothesis while punctual impact of the spill on survival and expanded (3. years) impact alternatives received less support. The effect size of the spill on averaged survival estimates was negligible in every case. We suggest that petrels minimized the impact of acute pollution by not investing in reproduction. We suggest that short-medium term management actions after oil-spills and similar catastrophes should focus on ecosystem restoration.
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    Ecological risk assessment of contaminated soils through direct toxicity assessment
    (2005-10) Fernández, María Dolores; Cagigal, Ekain; Vega, María Milagrosa; Urzelai, Arantzazu; Babín, Mar; Pro, Javier; Tarazona, José Vicente; TRAZABILIDAD CIRCULAR; Centros PRE-FUSION TECNALIA - (FORMER)
    A microcosm (MS-3) with a multispecies soil system is introduced as an experimental tool for direct toxicity assessment of contaminated soils. The capacity of MS-3 to determine soil ecotoxicity potential was evaluated using samples from three sites contaminated with organic and/or inorganic compounds. Soils were toxic to soil-dwelling organisms (earthworm, plants, and microorganisms) and to aquatic organisms (algae and RTG-2 cell fish). As expected, responses varied substantially among different soils and organisms. The application of this evaluation system provided complementary information to the chemical characterization. For soils containing metals the toxic response was lower than predicted from total metal concentrations. For hydrocarbons, the toxicity response agreed with estimated values. The induction of EROD activity suggested the presence of dioxin-like compounds, which had not been addressed in the chemical characterization. The proposed multispecies system affords the measurement of 11 endpoints covering three soil and three aquatic taxonomic groups, reproduces soil conditions and gradients, and appears as an excellent complementary tool to chemical analysis for characterization of contaminated sites.
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    The effect of nanosilica (SiO2) and nanoalumina (Al2O3) reinforced polyester nanocomposites on aerosol nanoparticle emissions into the environment during automated drilling
    (2017-05) Starost, Kristof; Frijns, Evelien; Van Laer, Jo; Faisal, Nadimul; Egizabal, Ainhoa; Elizetxea, Cristina; Nelissen, Inge; Blázquez, María; Njuguna, James; Biomateriales; POLIMEROS
    The aim of this study is to investigate the effect nanosilica and nanoalumina has on nanoparticle release from industrial nanocomposites due to drilling for hazard reduction whilst simultaneously obtaining the necessary mechanical performance. This study is therefore specifically designed such that all background noise is eliminated in the measurements range of 0.01 particles/cm3 and ±10% at 106 particles/cm3. The impact nano-sized SiO2 and Al2O3 reinforced polyester has on nanoparticle aerosols generated due to drilling is investigated. Real-time measurement was conducted within a specially designed controlled test chamber using a condensation particle counter (CPC) and a scanning mobility particle sizer spectrometer (SMPS). The results show that the polyester nanocomposite samples displayed statistically significant differences and an increase in nanoparticle number concentration by up to 228% compared to virgin polyester. It is shown that the nanofillers adhered to the polyester matrix showing a higher concentration of larger particles released (between 20 – 100 nm). The increase in nanoparticle reinforcement weight concentration and resulting nanoparticle release vary considerably between the nanosilica and nanoalumina samples due to the nanofillers presence. This study indicates a future opportunity to safer by design strategy that reduces number of particles released concentration and sizes without compromising desired mechanical properties for engineered polymers and composites.
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    Effects of Orientations, Aspect Ratios, Pavement Materials and Vegetation Elements on Thermal Stress inside Typical Urban Canyons
    (2019-09) Lobaccaro, G.; Acero, J.A.; Sanchez, G.; Padro, A.; Laburu, T.; Fernandez, G.; Martinez, Gerardo Sanchez; Tecnalia Research & Innovation; CALIDAD Y CONFORT AMBIENTAL
    The analysis of local climate conditions to test artificial urban boundaries and related climate hazards through modelling tools should become a common practice to inform public authorities about the benefits of planning alternatives. Different finishing materials and sheltering objects within urban canyons (UCs) can be tested, predicted and compared through quantitative and qualitative understanding of the relationships between the microclimatic environment and subjective thermal assessment. This process can work as support planning instrument in the early design phases as has been done in this study that aims to analyze the thermal stress within typical UCs of Bilbao (Spain) in summertime through the evaluation of Physiologically Equivalent Temperature using ENVI-met. The UCs are characterized by different orientations, height-to-width aspect ratios, pavement materials, trees’ dimensions and planting pattern. Firstly, the current situation was analyzed; secondly, the effects of asphalt and red brick stones as streets’ pavement materials were compared; thirdly, the benefits of vegetation elements were tested. The analysis demonstrated that orientation and aspect ratio strongly affect the magnitude and duration of the thermal peaks at pedestrian level; while the vegetation elements improve the thermal comfort up to two thermophysiological assessment classes. The outcomes of this study, were transferred and visualized into green planning recommendations for new and consolidated urban areas in Bilbao.
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    Efficient Ullmann and Suzuki-Miyaura cross-coupling reactions catalyzed by heterogeneous Pd-porous carbon beads catalysts in aqueous media
    (2022-12) Khosravi, Faezeh; Centeno-Pedrazo, Ander; Rajabi, Fatemeh; Len, Thomas; Voskressensky, Leonid G.; Luque, Rafael; Garcia-Suarez, Eduardo J.; Tecnalia Research & Innovation
    Carbon-carbon coupling reactions are of great interest for a wide range of applications including pharmaceutical compounds and biologically active molecules. Usually, coupling reactions were performed using a homogeneous catalyst and organic solvent. Thus, the use of greener solvents as well as the heterogenization of the classical metal-based catalyst are desirable and still under development. This contribution describes the synthesis of biaryl compounds in water by Ullmann and Suzuki reactions with carbon-supported Pd nanoparticles. As expected, the microwave activation method drastically decrease the reaction time. The utilization of trioctylphosphine (TOP) or triphenylphosphine (TPP) ligands slow down the Pd leaching without cancelling it compared to the unliganded Pd catalyst. Moreover, a treatment with H2O2 appears beneficial with respect to a thermal-oxidative treatment at 1500 °C due to higher hydrophilicity of the resultant carbon support. These results and methodology contribute to a greener future for C–C coupling reactions.
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    Electrosynthesis of 2,3-butanediol and methyl ethyl ketone from acetoin in flow cells
    (2019) Ochoa-Gómez, José R.; Fernández-Carretero, Francisco; Río-Pérez, Francisca; García-Luis, Alberto; Roncal, Tomás; García-Suárez, Eduardo J.; Tecnalia Research & Innovation; TECNOLOGÍAS DE HIDRÓGENO; BIOECONOMÍA Y CO2
    Acetoin could shortly become a platform molecule due to current progress in fermentation technology, the megatrend for shifting from an oil-based economy to one based on biomass, the quest for green manufacturing processes and its two highly reactive carbonyl and hydroxyl moieties. In this paper, the successful electro-conversion of acetoin into two valuable chemicals, 2,3-butandiol (2,3-BD) and methyl ethyl ketone (MEK), at constant electrical current in aqueous phase at room temperature using both divided and undivided 20 cm2 filter-press flow cells under experimental conditions suitable for industrial production is reported. Cathode material is the key parameter to drive the electroreduction towards one or another chemical. 2,3-BD is the major chemical produced by electrohydrogenation when low hydrogen overvoltage cathodes, such as Pt and Ni, of high surface area obtained by PVD coating on a carbon gas diffusion layer are used, while MEK is the principal product produced by electrohydrogenolysis when high hydrogen overvoltage cathodes, such as graphite, Pb and Cd foils, are employed. 2,3-BD and MEK can be obtained, respectively, in 92.8% and 85.7% selectivities, 71.7% and 80.4% current efficiencies, with 1.21 and 1.08 kg.h-1.m-2 productivities and power consumptions of 2.94 and 4.1 kWh.kg-1 using undivided cells and aqueous K2HPO4 electrolysis media at pHs of 3.6 and 5.5. The reported electroconversion of acetoin is highly flexible because 2,3-BD and MEK can be produced by changing just the cathode but using the same cell, with the same electrolyte at the same current density.
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    End-effector for automatic shimming of composites
    (2016-09-27) Antolín-Urbaneja, Juan Carlos; Livinalli, Juan; Puerto, Mildred; Liceaga, Mikel; Rubio, Antonio; San-Román, Angel; Goenaga, Igor; Tecnalia Research & Innovation; ROBOTICA_AUTOMA; FACTORY; INNOV_AIR_MOBIL; FABRIC_INTEL; MAQUINAS
    Gaps in composite structures are a risky factor in aeronautical assemblies. For mechanically joined composite components, the geometrical conformance of the part can be problematic due to undesired or unknown re-distribution of loads within a composite component, with these unknowns being potentially destructive. To prevent unnecessary preloading of a metallic structure, and the possibility of cracking and delamination in a composite structure, it is important to measure all gaps and then shim any gaps greater than 127 microns. A strategy to overcome the high relative tolerances for assemblies lies in the automated manufacturing of shims for the gaps previously predicted through the evaluation of their volumes via a simulation tool. This paper deals with the development of a special end-effector prototype to enable the shimming of gaps in composites structures using a pre-processed geometry. The aim of this end-effector is to provide movement to a temperature controlled hot-end in order to generate a solid shim of ABS on the target composite surface. This process is defined according to the trajectories and velocities marked by the 3D printing process using standard G-code. The geometry and material volume to be printed are indicated by the simulated gap volume which is based on previous metrological measurements. The final objective will be to attach this end-effector to an anthropomorphic robot to enable autonomous manufacturing. This work is part of the EU FP7 funded LOCOMACHS project, under grant agreement n◦314003.