Browsing by Keyword "General Chemical Engineering"
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Item Bacterial-cellulose-derived carbonaceous electrode materials for water desalination via capacitive method: The crucial role of defect sites: The crucial role of defect sites(2020-10-15) Belaustegui, Yolanda; Pantò, Fabiola; Urbina, Leire; Corcuera, Maria Angeles; Eceiza, Arantxa; Palella, Alessandra; Triolo, Claudia; Santangelo, Saveria; VALORIZACIÓN DE RESIDUOSElectrosorptive desalination is a very simple and appealing approach to satisfy the increasing demand for drinking water. The large-scale application of this technology calls for the development of easy-to-produce, cheap and highly performing electrode materials and for the identification and tailoring of their most influential properties, as well. Here, biosynthesised bacterial cellulose is used as a carbon precursor for the production of three-dimensional nanostructures endowed with hierarchically porous architecture and different density and type of intrinsic and hetero-atom induced lattice defects. The produced materials exhibit unprecedented desalination capacities for carbon-based electrodes. At an initial concentration of 585 mg L−1 (10 mmol L−1), they are able to remove from 55 to 79 mg g−1 of salt; as the initial concentration rises to 11.7 g L−1 (200 mmol L−1), their salt adsorption capacity reaches values ranging between 1.03 and 1.35 g g−1. The results of the thorough material characterisation by complementary techniques evidence that the relative amount of oxygenated surface functional species enhancing the electrode wettability play a crucial role at lower NaCl concentrations, whereas the availability of active non-sp2 defect sites for adsorption is mainly influential at higher salt concentrations.Item Development of highly permeable ultra-thin Pd-based supported membranes(2016-12-01) Fernandez, Ekain; Sanchez-Garcia, Jose Angel; Melendez, Jon; Spallina, Vincenzo; van Sint Annaland, Martin; Gallucci, Fausto; Pacheco Tanaka, D. A.; Prema, Radha; TECNOLOGÍAS DE HIDRÓGENO; Tecnalia Research & Innovation; TECNOLOGÍA DE MEMBRANAS E INTENSIFICACIÓN DE PROCESOSThis paper reports the preparation and characterization of ultra-thin (∼1 μm thick) Pd-based supported membranes for hydrogen purification. Ultra-thin membranes have been prepared by a combination of PVD magnetron sputtering and electroless plating techniques. The membranes have been characterized for single gas and mix gas permeation at temperatures between 350 and 500 °C and they have shown to exhibit very high hydrogen fluxes combined with a good perm-selectivity (H2/N2 ≈ 500). These results have been compared with the performance of highly permeable membranes reported in the literature. The influence of the morphology of the deposited Pd-based layers on the membrane performance has been investigated and discussed.Item Effect of the catalyst system on the reactivity of a polyurethane resin system for RTM manufacturing of structural composites(2022-03) Echeverria-Altuna, Oihane; Ollo, Olatz; Calvo-Correas, Tamara; Harismendy, Isabel; Eceiza, Arantxa; Tecnalia Research & Innovation; POLIMEROSThe high versatility of polyurethanes (PU’s) is encouraging the development of new formulations for new appli cations, like their use as a matrix for structural composites. PU’s based technology offers some advantages, such as fatigue resistance and fast curing cycles. However, their high reactivity hinders some manufacturing processes like Resin Transfer Moulding (RTM). This work aimed to achieve a PU resin (PUR) formulation with the required latency and reactivity for the RTM. For this purpose, different catalytic systems based on an epoxide and LiCl were investigated. The reactivity of the systems was evaluated through Differential Scanning Calorimetry (DSC) and rheology tests, and the curing reaction and viscosity were modelled. Furthermore, the RTM process of a representative composite part was simulated. Results demon strated the processability improvements when the LiCl was incorporated into the isocyanate component of the formulation combined with a monool or a diol. It was observed that these combinations contribute to the encapsulation of the LiCl between the as formed urethane groups by hydrogen bonding, providing the desired latency and acting as a delayed action catalyst. Once the reaction started and the encapsulation was deactivated, an alkoxide was formed to act as a catalyst. En capsulation was more effective with the diol, providing a higher latency.Item Electro-spun graphene-enriched carbon fibres with high nitrogen-contents for electrochemical water desalination(2018-02-15) Belaustegui, Yolanda; Zorita, Saioa; Fernández-Carretero, Francisco; García-Luis, Alberto; Pantò, Fabiola; Stelitano, Sara; Frontera, Patrizia; Antonucci, Pierluigi; Santangelo, Saveria; Tecnalia Research & Innovation; VALORIZACIÓN DE RESIDUOS; ADAPTACIÓN AL CAMBIO CLIMÁTICO; TECNOLOGÍAS DE HIDRÓGENOElectro-spun carbon fibres doped with very high nitrogen concentrations (19–21 wt%) are obtained operating carbonisation at low temperature (500 °C). The as-synthesised fibres are evaluated as electrode materials for the electrochemical desalination of water. The effect of the enrichment of the nitrogen doped carbon fibres with thermally reduced graphene oxide is also investigated. The fibrous electrodes are able to remove amazing amounts of NaCl (17.0–27.6 mg/g) from a salty solution with an initial concentration of 585 mg/L. The nitrogen doping, which dramatically improves the wettability, plays a crucial role in determining the outstanding electro-sorption capacities of the fibres. It allows fully profiting of the more favourable pore size distribution in the graphene-enriched fibres, endowed with higher conductivity and capacitance, for the obtainment of unprecedented electro-sorption capacities via an extremely simple synthesis process, with no need of activation treatments.Item Evaluation of the electrochemical performance of electrospun transition metal oxide-based electrode nanomaterials for water CDI applications(2019-06-20) Santangelo, Saveria; Pantò, Fabiola; Triolo, Claudia; Stelitano, Sara; Frontera, Patrizia; Fernández-Carretero, Francisco; Rincon, Inés; Azpiroz, Patxi; García-Luis, Alberto; Belaustegui, Yolanda; Tecnalia Research & Innovation; TECNOLOGÍAS DE HIDRÓGENO; VALORIZACIÓN DE RESIDUOSComposite fibrous materials based on (graphene-enriched) nitrogen-doped carbon/transition metal oxides were produced by electrospinning and their physicochemical properties were thoroughly investigated by a combination of characterisation techniques. The electrochemical behaviour of the electrodes prepared with them was evaluated in view of their use in the capacitive deionisation of saline water. The morphology of the materials reminded of usnea florida lichens, wheat ears, sea sponges and noodles and depended on the transition metal (Mn, Fe, Ti or Zn). The morphology and the relative amount (14.1–22.2 wt%) of the surface nitrogen and carbon-bonded oxygen functional species, beneficial to wettability and involving pseudocapacitive processes, had strong impact on the specific capacitance (43.7–67.4 F g−1, at 5 m V s−1 scan rate), whereas also the specific micropore volume (0.4–5.6 mm3 g−1) affected the effective areal capacitance of the electrodes (1.2–6.0 F m−2, at 5 mV s−1). Ion storage in the composite materials occurred via a mixed capacitive/pseudocapacitive process. Hence, increasing the content of the oxide (from 24.6 to 56.7 wt%), thanks to the fast-reversible redox reactions at or near surface it involves, partly compensated for the growing hindrance to diffusion encountered by the ions (hampered electrostatic adsorption) as the scan rate increased from 5 to 100 mV s−1.Item Experimental investigation of electric discharge parameters in correlation with peak pressure at industrial electrohydraulic forming(2019-10) Pérez, I.; Knyazyev, M. K.; San José, J.; PROMETALThe paper shows the investigation results of correlating electric discharge and pressure field parameters aimed to improvements in the electrohydraulic impact forming (EHF) technology at industrial application. The experimental research was performed by using a conical discharge chamber equipped with a set of two electrodes in semi-industrial EHF installation. Pressure fields along round flat area were measured by applying the multi-point membrane pressure gauge methodology. The conditions of the tests include a wide range of spark gaps with four levels of charge voltage and energy. Measurements of discharge voltage and current are performed with voltage divider, Rogovsky coil and electronic oscilloscope. Other electric discharge parameters were calculated from the recorded voltage and current curves. The essence of investigation is to analyse energy parameters for peak pressure of shock wave generated by these discharge energy parameters. Though these dependencies were earlier analysed theoretically and tested in electrohydraulic plants under laboratory conditions, the practical interest in this experimental investigation is to reveal influence of conditions of real semi-industrial EHF press designed for batch production of sheet parts. Conducted experimental investigation has shown that industrial applications of high-voltage non-initiated discharges can significantly deviate from the theoretical and laboratory results. Dependencies of peak pressure from maximum power during the first semi-period of discharge current and slope of power curve appeared to be not so strong. These deviations in peak pressure can reach 20–30%. Among the assumed additional factors influencing energy and pressure parameters are: condition of current-conductive rod of electrode (erosion, rust, radius); condition (wear) of electrode insulator (increase of naked area of current-conductive rod); variations in shape, position and length of discharge channel relative to spark gap; “shadowing” effect of electrodes at some positions of discharge channel relative to electrode;, several discharge channels at small spark gap and other. To reveal effect of these factors the authors plan to carry-out tests with wire-initiated discharges to check the variations in shape, position and length of discharge channel relative to spark gap in the same discharge chamber configuration.Item Fate of NO and Ammonia in Chemical Looping Combustion─Investigation in a 300 W Chemical Looping Combustion Reactor System(2022-09-01) Lyngfelt, Anders; Hedayati, Ali; Augustsson, Ellen; Tecnalia Research & InnovationChemical looping combustion (CLC) is a novel combustion concept that transfers oxygen from air to fuel using an oxygen carrier that circulates between an air reactor and a fuel reactor. Thus, the combustion products, H2O and CO2, are obtained in a separate flow, and ideally, a pure CO2 gas stream is obtained after condensation of H2O. Consequently, CLC has a unique potential for avoiding the high costs and energy penalties of CO2 capture. Further, NO emissions can potentially be avoided. CLC is flameless, and the temperature is too low for the formation of thermal NOx. Moreover, fuel NOx and prompt NOx do not form in the air reactor in the absence of fuel. In the fuel reactor, the absence of oxygen prevents normal NOx formation. However, when using fuels containing nitrogen, NO may form in the fuel reactor because the oxygen carrier can oxidize fuel nitrogen compounds. To achieve a CO2 stream suited for storage, NO must be removed. Dependent upon how NO is removed, the process could be free from any NO emissions. NO formation and NO reduction were investigated in a 300 W CLC reactor by adding either NH3 or NO. The work involved two different oxygen carriers, Linz–Donawitz (LD) slag and ilmenite, two temperatures, 850 and 900°C, two circulation rates, and different flows of syngas fuel. Further, operation without fuel with a fully and partially oxidized oxygen carrier was studied. For LD slag, lower fuel flow promoted the formation of NO and decreased the reduction of NO. Likewise, higher temperatures raised NO formation and lowered NO reduction. Ilmenite, however, was by far more superior with respect to NO. Thus, NO formation only occurred in the absence of fuel and with a fully oxidized oxygen carrier. Likewise, NO was fully reduced to N2 for all conditions, except in the absence of fuel and with fully oxidized ilmenite.Item H2 production via ammonia decomposition in a catalytic membrane reactor(2021-06-01) Cechetto, Valentina; Di Felice, Luca; Medrano, Jose A.; Makhloufi, Camel; Zuniga, Jon; Gallucci, Fausto; TECNOLOGÍA DE MEMBRANAS E INTENSIFICACIÓN DE PROCESOSThe membrane reactor is proposed in this work as a system with high potential to efficiently recover the hydrogen (H2) stored in ammonia (NH3), which has been recently proposed as an alternative for H2 storage. With this technology, NH3 decomposition and high-purity H2 separation are simultaneously performed within the same unit, and high H2 separation efficiency is achieved at lower temperature compared to conventional systems, leading to energetic and economic benefits. NH3 decomposition was experimentally performed in a Pd-based membrane reactor over a Ru-based catalyst and the performance of the conventional packed bed reactor were used as benchmark for a comparison. The results demonstrate that the introduction of a membrane in a conventional reactor enhances its performance and allows to achieve conversion higher than the thermodynamic equilibrium conversion for sufficiently high temperatures. For temperatures from and above 425 °C, full NH3 conversion was achieved and more than 86% of H2 fed to the system as ammonia was recovered with a purity of 99.998%. The application of vacuum at the membrane permeate side leads to higher H2 recovery and NH3 conversions beyond thermodynamic restrictions. On the other hand, the reactor feed flow rate and operating pressure have not shown major impacts on NH3 conversion.Item The Indus3Es Project: New technologies for Utilization of Heat Recovery in Large Industrial Systems: New technologies for utilization of heat recovery in large industrial systems(Avestia Publishing, 2017) Circelli, Patrizia; Cinti, Valentina; Alonso, Laura; Martinez, Asier; SISTEMAS TÉRMICOS EFICIENTESThe Indus3Es project received funding under H2020-EE-18-2015: New technologies for utilization of heat recovery in large industrial systems, considering the whole energy cycle from heat production to transformation, delivery and end use. Funded under the Grant Agreement 680738, the main objective of the project is to develop an economically viable solution for industry, appropriate for existing plants and adaptable to various industrial processes, consisting on the technology of Absorption Heat Transformer. The developed system will be demonstrated in real environment in Tu¨pras, the main petrochemical industry in Turkey, enabling to analyze besides integration aspects, operational and business issues. Indus3Es System will be defined and optimized for different specificities in different sectors and industrial processes, for which up-scaling of the demonstrated technology and replication studies will be performed.Item Integrated process for the recovery of yttrium and europium from CRT phosphor waste(2019) Forte, Federica; Yurramendi, Lourdes; Aldana, José Luis; Onghena, Bieke; Binnemans, Koen; VALORIZACIÓN DE RESIDUOSAn integrated process flow sheet for the recovery of yttrium and europium from waste cathode-ray tube (CRT) phosphors was developed. This flow sheet is based on a sequence of roasting, leaching with organic acids and precipitation steps. Zinc was efficiently removed from the roasted CRT phosphors by leaching with acetic acid, giving access to the rare earth content. Yttrium and europium were quantitatively leached from the residue by a 1 mol L−1 methanesulphonic acid (MSA) solution. Precipitation with oxalic acid gave a mixed Y/Eu oxalate of high purity (>99 wt%). Co-precipitation of zinc was less than 2 wt%.Item Isosorbide bis(methyl carbonate) synthesis from isosorbide and dimethyl carbonate: the key role of dual basic–nucleophilic catalysts: The key role of dual basic-nucleophilic catalysts(2020-05-18) Ochoa-Gómez, José R.; Lorenzo-Ibarreta, Leire; Diñeiro-García, Cristina; Gómez-Jiménez-Aberasturi, Olga; Tecnalia Research & Innovation; BIOECONOMÍA Y CO2; VALORIZACIÓN DE RESIDUOSIsosorbide bis(methyl carbonate) (IBMC) is a scarcely studied green chemical with potential applications in the manufacturing of non-isocyanate polyurethanes and bisphenol A-free polycarbonates. Its synthesis by transesterification of isosorbide with dimethyl carbonate (DMC) is very negatively influenced by the presence of small amounts of acidic impurities in isosorbide when heterogeneous inorganic carbonates such as potassium and cesium carbonates are used as catalysts. In this paper it is shown that the problem can be solved by using homogeneous catalysts consisting of nitrogenated bases and superbases having a suitable dual nucleophilic–basic character and able to form a highly reactive acyl intermediate with the electrophilic reactant DMC. Cycloaliphatic secondary and tertiary amines, guanidines and amidines covering a nucleophilicity parameter (N) range between 13.58 and 20.58 in either acetonitrile or dichloromethane, and a pKa range in acetonitrile between 15.68 and 26.02 have been tested in batchwise mode. Highly active catalysts leading to hydroxyl conversions of 84–93% require a minimum N of 16 and a pKa ranging from 18.0 to 26.0. Within this pKa range, N must increase by about 0.5–0.6 units per each unit the pKa falls to keep the catalytic activity, indicating that nucleophilicity has approximately twice as much influence as basicity on the catalytic activity. One guanidine (TBD), one amidine (DBN) and three cycloaliphatic secondary amines (N-methylpyrrolidine, quinuclidine and DABCO) have been found to be excellent catalysts at 5 mol% vs. ISO. The side reaction leading to oligomer formation is not avoided, with oligomers, mainly the dimer, affording 6 wt% of the crude product independently of hydroxyl-conversion and catalyst type.Item MOF-polymer enhanced compatibility: Post-annealed zeolite imidazolate framework membranes inside polyimide hollow fibers(2016) Cacho-Bailo, Fernando; Caro, Guillermo; Etxeberría-Benavides, Miren; Karvan, Oʇuz; Téllez, Carlos; Coronas, Joaquín; TECNOLOGÍA DE MEMBRANAS E INTENSIFICACIÓN DE PROCESOS; Tecnalia Research & InnovationThermal annealing, a commonly used procedure for improving the performance of polymeric membranes, is in this work exploited in the presence of a metal-organic framework (MOF) supported layer. MOFs and polymers are materials with a common organic character, suggesting an enhanced affinity between them when used together in membrane separation. Zeolite-like imidazolate frameworks (ZIFs) ZIF-8 and ZIF-93 with sod and rho structures and pore apertures of 0.34 and 0.36 nm, respectively, have been grown inside 356 μm OD co-polyimide P84 hollow fibers by microfluidics, leading to continuous supported membranes. When these membranes were thermally in situ annealed below the glass transition temperature, while monitoring both H2 and CH4 permeances, the MOF-polymer adhesion was enhanced. Thus the gas separation selectivity increased without any significant reduction in the gas permeance, and H2/CH4 and CO2/CH4 maximum selectivities of 103 and 18 (ZIF-8) and 101 and 20 (ZIF-93) were respectively measured. The good compatibility between MOF and polymer made improvements possible in the annealing of the membrane once it was prepared. If the annealing of the polymer was carried out before the MOF synthesis, the polymer chain rearrangement and surface smoothing prevented an optimum MOF-polymer interaction and the separation performance worsened. These results proved the compatibility between both materials and their synergistic contribution to gas selective transport.Item New hydrophilic carbon molecular sieve membranes for bioethanol dehydration via pervaporation(2022-05-01) Rahimalimamaghani, A.; Pacheco Tanaka, D.A.; Llosa Tanco, M.A.; Neira D'Angelo, F.; Gallucci, F.; TECNOLOGÍA DE MEMBRANAS E INTENSIFICACIÓN DE PROCESOSTubular supported carbon molecular sieve membranes (CMSMs) with high hydrophilicity and perm-selectivities for water suitable for ethanol dehydration were developed from a Novolac oligomer phenolic resin as precursor. Alpha alumina supported CMSMs resulted in 1.69 times higher surface roughness than zirconia supports. The higher surface roughness resulted in 48% higher selective layer thickness. According to pervaporation results, water permeance decreased by the increase in selective layer thickness and mole based selectivity of water- ethanol was enhanced. The oligomer with 3982 g/mol molecular weight enabled membrane to reach high selectivity with one-layer coating. Performance of the membranes are compared with literature data in terms of mole-based selectivity vs. water permeance. CMSMs could be a potential substitution for traditional ethanol dehydration methods with offering higher performance and as a result reducing the final price of bioethanol to be used as a sustainable energy source.Item Novel Concept of Micro Patterned Micro Titer Plates Fabricated via UV-NIL for Automated Neuronal Cell Assay Read-Out(2021-04-01) Lohse, Mirko; Thesen, Manuel W.; Haase, Anja; Smolka, Martin; Iceta, Nerea Briz; Ayerdi Izquierdo, Ana; Ramos, Isbaal; Salado, Clarisa; Schleunitz, Arne; Tecnalia Research & Innovation; SG; BiomaterialesThe UV-nanoimprint lithography(UV-NIL) fabrication of a novel network of micron-sized channels, forming an open channel microfluidic system is described. Details about the complete manufacturing process, from mastering to fabrication in small batches and in high throughput with up to 1200 micro titer plates per hour is presented. Deep insight into the evaluation of a suitable UV-curable material, mr-UVCur26SF is given, presenting cytotoxic evaluation, cell compatibility tests and finally a neuronal assay. The results indicate how the given pattern, in combination with the resist, paves the way to faster, cheaper, and more reliable drug screening.Item NPG–TRIS Thermal Storage System. Quantification of the Limiting Processes: Sublimation and Water’s Adsorption: Sublimation and water’s adsorption(2021-10-05) De La Pinta, Noelia; Santos-Moreno, Sergio; Doppiu, Stephania; Igartua, Josu M.; Palomo del Barrio, Elena; López, Gabriel A.; Tecnalia Research & Innovation; BIOECONOMÍA Y CO2The NPG–TRIS binary system (NPG = (CH3)2C(CH2OH)2 = 2,2-dimetyl-1,3-propanodiol; TRIS = NH2C(CH2OH)3 = 2-Amino-2-(hydroxymethyl)-1,3-propanediol) was intensively investigated as a thermal energy storage system, due to the reversibility of its phase transitions and their associated energy. An adapted methodology was applied to precisely quantify its sublimation tendency. Relevant thermochemical data were revisited and evaluated using some specific experimental procedures. We also determined that the widely accepted requirement of working in an inert atmosphere to avoid deviations due to hygroscopicity is not necessary. Nevertheless, to take advantage of the energetic properties of the NPG–TRIS system, closed containers will be required to avoid NPG losses, due to its quantitatively determined high sublimation tendency.Item On concentration polarisation in a fluidized bed membrane reactor for biogas steam reforming: modelling and experimental validation: Modelling and experimental validation(2018-09-15) de Nooijer, Niek; Gallucci, Fausto; Pellizzari, Emma; Melendez, Jon; Pacheco Tanaka, David A.; Manzolini, Giampaolo; van Sint Annaland, Martin; Tecnalia Research & Innovation; TECNOLOGÍA DE MEMBRANAS E INTENSIFICACIÓN DE PROCESOSThe production of pure hydrogen through the steam reforming of biogas in a fluidized bed membrane reactor has been studied. A phenomenological one-dimensional two-phase fluidized bed reactor model accounting for concentration polarisation with a stagnant film model has been developed and used to investigate the system performance. The validation of the model was performed with steam reforming experiments at temperatures ranging from 435 °C up to 535 °C, pressures between 2 to 5 bar and CO2/CH4 ratios up to 0.9. The permeation performance of the ceramic-supported PdAg thin-film membrane was first characterized separately for both pure gas and gas mixtures. Subsequently, the membrane was immersed into a fluidized bed containing Rh supported on alumina particles and the reactor performance, viz. the methane conversion, hydrogen recovery and hydrogen purity, was evaluated under biogas steam reforming conditions. The resulting hydrogen purity under biogas steam reforming conditions was up to 99.8%. The model results were in very good agreement with the experimental results, when assuming a thickness of the stagnant mass transfer boundary layer around the membrane equal to 0.54 cm. It is shown that the effects of concentration polarisation in a fluidized bed membrane reactor can be well described with the implementation of a film layer description in the two-phase model.Item On the Use of Carbon Cables from Plastic Solvent Combinations of Polystyrene and Toluene in Carbon Nanotube Synthesis(2021-12-21) Orbaek White, Alvin; Hedayati, Ali; Yick, Tim; Gangoli, Varun Shenoy; Niu, Yubiao; Lethbridge, Sean; Tsampanakis, Ioannis; Swan, Gemma; Pointeaux, Léo; Crane, Abigail; Charles, Rhys; Sallah-Conteh, Jainaba; Anderson, Andrew O.; Davies, Matthew Lloyd; Corr, Stuart. J.; Palmer, Richard E.; Tecnalia Research & InnovationFor every three people on the planet, there are approximately two Tonnes (Te) of plastic waste. We show that carbon recovery from polystyrene (PS) plastic is enhanced by the coaddition of solvents to grow carbon nanotubes (CNTs) by liquid injection chemical vapour deposition. Polystyrene was loaded up to 4 wt% in toluene and heated to 780 °C in the presence of a ferrocene catalyst and a hydrogen/argon carrier gas at a 1:19 ratio. High resolution transmission electron microscopy (HRTEM), scanning electron microscopy (SEM), thermogravimetric analysis (TGA) and Raman spectroscopy were used to identify multiwalled carbon nanotubes (MWCNTs). The PS addition in the range from 0 to 4 wt% showed improved quality and CNT homogeneity; Raman “Graphitic/Defective” (G/D) values increased from 1.9 to 2.3; mean CNT diameters increased from 43.0 to 49.2 nm; and maximum CNT yield increased from 11.37% to 14.31%. Since both the CNT diameters and the percentage yield increased following the addition of polystyrene, we conclude that carbon from PS contributes to the carbon within the MWCNTs. The electrical contact resistance of acid-washed Bucky papers produced from each loading ranged from 2.2 to 4.4 Ohm, with no direct correlation to PS loading. Due to this narrow range, materials with different loadings were mixed to create the six wires of an Ethernet cable and tested using iPerf3; the cable achieved up- and down- link speeds of ~99.5 Mbps, i.e., comparable to Cu wire with the same dimensions (~99.5 Mbps). The lifecycle assessment (LCA) of CNT wire production was compared to copper wire production for a use case in a Boeing 747-400 over the lifespan of the aircraft. Due to their lightweight nature, the CNT wires decreased the CO2 footprint by 21 kTonnes (kTe) over the aircraft’s lifespan.Item Polyurethane/acrylic hybrid dispersions containing phosphorus reactive flame retardants as transparent coatings for wood(2022-09) Puyadena, M.; Etxeberria, I.; Martin, L.; Mugica, A.; Agirre, A.; Cobos, M.; Gonzalez, A.; Barrio, A.; Irusta, L.; BIOECONOMÍA Y CO2Phosphorus modified polyurethane/acrylic hybrid dispersions were prepared for flame retardant transparent wood coatings. The polymerisation was carried out in three steps. In the first one, the polyurethane was synthesised using an acrylic monomer as solvent. The second step involved water addition that promoted the phase inversion and lastly, acrylic part was polymerised. The phosphorous compounds were covalently linked to polyurethane using a phosphorylated polyol and to the acrylic phase using an acrylic phosphate. Polymerisation was monitored by FTIR and NMR and the molar mass of the hybrids was measured by AF4 and SEC. The effects of the phosphorus in fire-retardant properties were analysed by thermogravimetry and pyrolysis combustion flow calorimetry. The introduction of phosphorus did not produce significant changes in the polymerisation process but promoted the cross-linking of the coatings. The coated wood samples maintained the transparency and good properties with the introduction of phosphorus and presented a slight reduction in the Peak Heat Release Rate measured by cone calorimeter. The action of phosphorus as a fire retardant was effective as it gave rise to significant reduction of the CO and CO2 peaks.Item Preparation and characterization of metallic supported thin Pd–Ag membranes for hydrogen separation(2016-12-01) Fernandez, Ekain; Medrano, Jose Antonio; Melendez, Jon; Parco, Maria; Viviente, Jose Luis; van Sint Annaland, Martin; Gallucci, Fausto; Pacheco Tanaka, D. A.; TECNOLOGÍAS DE HIDRÓGENO; Tecnalia Research & Innovation; EXTREMAT; TECNOLOGÍA DE MEMBRANAS E INTENSIFICACIÓN DE PROCESOSThis paper reports the preparation and characterization of thin-film (4–5 μm thick) Pd–Ag metallic supported membranes for high temperature applications. Various thin film membranes have been prepared by depositing a ceramic interdiffusion barrier layer prior to the simultaneous Pd–Ag electroless plating deposition. Two deposition techniques for ceramic layers (made of zirconia and alumina) have been evaluated: Atmospheric Plasma Spraying and dip coating of a powder suspension. Initially, the prepared ceramic layers have been characterized for nitrogen permeation at room temperature and surface roughness for the selection of the appropriate type of ceramic layer. The most promising membranes have been tested at 400–600 °C for single gas permeation (H2 and N2), and have shown extremely high H2/N2 permselectivities (>200,000).Item Surface Energy and Lewis Acid-base Characteristics of Lignocellulosic Fibers upon Modification by Chemical Vapor Deposition of Trichloromethylsilane: An Inverse Gas Chromatography Study: An Inverse Gas Chromatography Study(2018-05-04) Gamelas, J. A. F.; Azpeitia, M.; Ferreira, P. J.; Tejado, A.; VALORIZACIÓN DE RESIDUOS; BIOECONOMÍA Y CO2The surface of a thermomechanical pulp (TMP), containing 26 wt% of lignin, was modified by silanization with trichloromethylsilane (TCMS) via chemical vapor deposition, and thoroughly analyzed for its physicochemical properties by inverse gas chromatography (attenuated total reflection-Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy being used as complementary tools). For a 2-min TCMS-treated TMP, a decrease of the dispersive component of the surface energy from 38 to 14 mJ m−2 (at 40°C), and, at the same time, an increase of the Lewis acidic and Lewis basic characters were found. The surface of this sample, modified in a high extent, was similar to that of a bleached kraft pulp (<0.1 wt% of lignin) subjected to the same silanization process, which is suggested as being due, in both cases, to the formation of a methyl-silica coating on the fiber’s surface. The new silanized fibers obtained from cheap TMP can be used for the production of a new generation of biocomposites with a variety of matrices.