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Polyurethane (PU) is one of the most versatile polymers available and can be found in an infinite number of formats ranging from rigid or flexible foams to elastomers. Currently, most Rigid PU Foam (RPUF) waste is landfilled, even though a small amount is mechanically recycled, in which the material is conditioned in size to a very fine powder, which is introduced as a filler. In this work, chemical recycling of two types of rigid PU foams is studied, the major difference being the aliphatic or aromatic nature of the isocyanate used in the synthesis. A solvolysis process is developed, a chemical depolymerization that breaks the chains by means of a chemical agent, a solvent, in the presence of a catalyst and under controlled process conditions. The glycolysis products are purified by vacuum distillation, centrifugation, and acid water treatment, depending on the most suitable process for each waste type. Optimal process conditions are established to obtain high-purity green polyols by performing a set of catalytic glycolysis reactions at laboratory scale with the previously conditioned RPUF waste samples. The physicochemical properties of the polyols, such as hydroxyl value, acid value, average molecular weight (Mn), and viscosity, are analyzed. The chemical structure and thermal stability of the polyols are studied by means of FTIR and TGA, respectively. Partial substitution of the commercial polyol (up to 15 wt.%) by the recycled polyols for RPUF synthesis is studied and characterized.

The aim of this paper is for the production of oils processed in refineries to come from the pyrolysis of real waste from the high plastic content rejected by the recycling industry of the Basque Country (Spain). Concretely, the rejected waste streams were collected from (1) a light packaging waste sorting plant, (2) the paper recycling industry, and (3) a waste treatment plant of electrical and electronic equipment (WEEE). The influence of pre-treatments (mechanical separation operations) and temperature on the yield and quality of the liquid fraction were evaluated. In order to study the pre-treatment effect, the samples were pyrolyzed at 460 °C for 1 h. As pre-treatments concentrate on the suitable fraction for pyrolysis and reduce the undesirable materials (metals, PVC, PET, inorganics, cellulosic materials), they improve the yield to liquid products and considerably reduce the halogen content. The sample with the highest polyolefin content achieved the highest liquid yield (70.6 wt.% at 460 °C) and the lowest chlorine content (160 ppm) among the investigated samples and, therefore, was the most suitable liquid to use as refinery feedstock. The effect of temperature on the pyrolysis of this sample was studied in the range of 430–490 °C. As the temperature increased the liquid yield increased and solid yield decreased, indicating that the conversion was maximized. At 490 °C, the pyrolysis oil with the highest calorific value (44.3 MJ kg−1) and paraffinic content (65% area), the lowest chlorine content (128 ppm) and more than 50 wt.% of diesel was obtained. This research was funded by the Basque Government through the project with reference KK-2020/00107 (ELKARTEK program) and through the support of the SUPREN group (GIC10/31, GIC15/13, S-PE13UN126 (SAI13/190)).

En este estudio analizaremos muestras representativas e inspiradoras de personajes masculinos y femeninos con discapacidad de la literatura contemporánea escrita en español que desafíen los arquetipos de masculinidad, feminidad y discapacidad preconcebidos, escasamente matizados y discriminatorios que aún perviven en las sociedades actuales. A saber, los protagonistas de Otra forma de mirar: memorias de un joven con síndrome de Asperger (Miguel Dorado, 2004), La mujer que buceó dentro del corazón del mundo (Sabrina Berman, 2012), El cuerpo en que nací (Guadalupe Nettel, 2011) y No creas lo que tus ojos te dicen (Javier Martín Betanzos, 2019). Nuestra investigación se sustentará sobre un análisis cualitativo y comparativo de los rasgos disidentes, realistas y disruptivos de las representaciones seleccionadas que cuestionen los modelos tradicionales y hegemónicos de hombre, mujer y persona con discapacidad en nuestras culturas. Así, en línea con las reivindicaciones de las nuevas corrientes en estudios de género y sobre discapacidad, abogaremos por una evolución nocional y social hacia percepciones más inclusivas de la diferencia que reconozcan y permitan construir representaciones e identidades diversas e interseccionales en espacios clave para la definición cultural, como la literatura. In this paper we shall analyse representative and inspiring examples of male and female characters with disabilities within contemporary literature written in Spanish that challenge the preconceived, discriminatory and scarcely comprehensive and currently dominant archetypes of masculinity, femininity and disability. Namely, the main characters of Otra forma de mirar: memorias de un joven con síndrome de Asperger (Miguel Dorado, 2004), La mujer que buceó dentro del corazón del mundo (Sabrina Berman, 2012), El cuerpo en que nací (Guadalupe Nettel, 2011) y No creas lo que tus ojos te dicen (Javier Martín Betanzos, 2019). Our research will be built upon a qualitative and comparative analysis of the dissenting, realistic and disruptive features of the selected characterizations that may question the traditional and hegemonic paradigmatic models of men, women and people with disabilities in our cultures. Thus, in line with new trends stemming from gender studies and disability studies, we shall advocate for a conceptual and social evolution towards more holistic perceptions of the difference which recognise and allow for diverse and intersectional representations and identities in fields of cultural production, such as literature.

The preparation and characteristics of rigid polyurethane foams (RPUFs) synthesized from polyols obtained by glycolysis of post-industrial waste RPUFs have been studied. More precisely, waste rigid foams that have been chemically recycled by glycolysis in this work are industrially produced pieces for housing and bracket applications. The glycolysis products have been purified by vacuum distillation. The physicochemical properties of the polyols, such as hydroxyl value, acid value, average molecular weight (Mn) and viscosity have been analyzed. The chemical structure and thermal stability of the polyols have been studied by means of FTIR and TGA, respectively. Partial substitution of the commercial polyol (up to 15 wt.%) by the recycled polyols increases the reactivity of the RPUFs synthesis, according to short characteristic times during the foaming process along with more exothermic temperature profiles. Foams formulated with recycled polyols have a lower bulk density (88.3–96.9 kg m−3) and smaller cell sizes compared to a conventional reference RPUF. The addition of recycled polyols (up to 10 wt.%) into the formulation causes a slight decrease in compressive properties, whereas tensile strength and modulus values increase remarkably.

Herein we present a high yield 2-methylfuran production process with the required features to be implemented in a future integrated biorefinery. The strategy is based on the right solvent selection, 2-methyltetrahydrofuran, which i) can be used to extract the reactant, furfural, from the aqueous solution obtained after corncob biomass hydrolysis; ii) allows for highly selective 2-methylfuran production form furfural with up to 80% yields and iii) presents suitable biofuel properties in the gasoline range. Using this innovative approach, two energy intensive separation steps are avoided: the initial furfural purification and the final solvent/product complete separation. Further benefits of this process arise from the developed low-cost, selective, and reusable Cu-Co/γ-Al2O3 catalyst.

Three aluminium oxide materials and a HZSM-5 zeolite were used as supports of bimetallic Pt-WOx catalysts, in order to establish structure-activity relationships in the glycerol hydrogenolysis reaction. The tungsten surface density and the intimate contact between Pt and WOx showed to be key parameters. Tungsten surface density controls the formation of polytungstates, the only species able to produce the weak Bronsted acidity that is required to selectively produce 1,3-propanediol. The comparison between the HZSM-5 and the Al2O3 supports demonstrated that an increment on the medium Bronsted acidity is detrimental for the selective 1,3-propanediol formation, as it promotes the reactions that yield 1-propanol and propane. Increasing the dispersion of Pt for the Pt/WOx/Al2O3 catalysts led to larger glycerol conversion values, but promoted the hydrogenolysis routes that lead to 1,2 and 1,3-propanediol similarly. On the contrary, increasing the Pt metal content significantly favoured the hydrogenolysis route leading to 1,3-propanediol. A more intimate contact between Pt and WOx promoted the hydrogenation of the intermediate carbocation, formed and stabilized on a polytungstate active site, into 1,3- propanediol.

SSCI-VIDE+ATARI+SGF:SBE:AAU; International audience; Although the hydrogenolysis of glycerol to 1,2-propanediol is already well developed, the production of the more valuable 1,3-propanediol is still a challenge. To achieve this aim, it is essential to design catalysts showing high selectivity toward the CO cleavage of the secondary hydroxyl group in glycerol. In this work, two different series of Pt/WOx/Al2O3 catalytic systems were studied for the selective hydrogenolysis of glycerol to 1,3-propanediol. The results reveal the necessity to control the tungsten surface density in order to obtain highly dispersed polytungstate species, which are able to produce Bronsted acidity and are involved in the selective formation of 1,3-propanediol. After optimization of the tungsten surface density, the effect of platinum content was also studied. It was found that by improving the interactions between platinum and tungsten oxides, it is possible to increase the selectivity toward 1,3-propanediol. Under optimized conditions, a selectivity toward 1,3-PDO of 51.9% at 53.1% glycerol conversion was obtained. Based on the characterization and activity test results, a reaction mechanism for the Pt-WOx catalytic system in glycerol hydrogenolysis to 1,3-propanediol was also proposed. (C) 2015 Elsevier Inc. All rights reserved.

La escritura de la aguja. Línea y sutura en la obra de Concha RomeuCon el objetivo de poner en valor la costura como técnica artística contemporánea, este artículo analiza a través de la obra de la artista Concha Romeu (Madrid, 1954) las dos bases que hacen del ejercicio de coser una forma de escritura: la línea y la sutura. La primera de ellas introduce el concepto de huella y la segunda nos conduce hacia una reflexión sobre la víctima.Palabras clave: Costura, escritura, huella, herida, víctima The writing of needle. Line and suture in the work of Concha RomeuIn order to value sewing as a contemporary artistic technique, this article analyzes through the work of the artist Concha Romeu (Madrid, 1954) the two basis that make sewing a way of writing: the line and the suture. The first one introduces the concept of trace, and the second leads us to the reflection on the victim.Key words: Sewing, writing, trace, wound, victim