Catalytic gasification of glycerol in supercritical water

The conversion of glycerol in supercritical water (SCW) was studied at 510-550 °C and a pressure of 350 bars using both a bed of inert and non-porous ZrO2 particles (hydrothermal experiments), and a bed of a 1% Ru/ZrO2 catalyst. Experiments were conducted with a glycerol concentration of 5 wt% in a continuous isothermal fixed-bed reactor at a residence time between 2 and 10 s. Hydrothermolysis of glycerol formed water-soluble products such as acetaldehyde, acetic acid, hydroxyacetone and acrolein, and gases like H2, CO and CO2. The catalyst enhanced the formation of acetic acid, inhibited the formation of acrolein, and promoted gasification of the glycerol decomposition products. Hydrogen and carbon oxides were the main gases produced in the catalytic experiments, with minor amounts of methane and ethylene. Complete glycerol conversion was achieved at a residence time of 8.5 s at 510 °C, and at around 5 s at 550 °C with the 1 wt% Ru/ZrO2 catalyst. The catalyst was not active enough to achieve complete gasification since high yields of primary products like acetic acid and acetaldehyde were still present. Carbon balances were between 80 and 60% in the catalytic experiments, decreasing continuously as the residence time was increased. This was attributed partially to the formation of methanol and acetaldehyde, which were not recovered and analyzed efficiently in our set-up, but also to the formation of carbon deposits. Carbon deposition was not observed on the catalyst particles but on the surface of the inert zirconia particles, especially at high residence time. This was related to the higher concentration of acetic acid and other acidic species in the catalytic experiments, which may polymerize to form tar-like carbon precursors. Because of carbon deposition, hydrogen yields were significantly lower than expected; for instance at 550 °C the hydrogen yield potential was only 50% of the stoichiometric value

Reportatge: Habitatges a la Plaça Europa

Un home culte i refinat (Gregory Peck) arriba a l’Oest americà. Serà rebut amb mensypreu i sense escrúpols, però malgrat aquesta “benvinguda”, Peck no s’alterarà el més mínim. A Grans horitzons, una pel·lícula on la història i el missatge van molt més enllà del gènere, es presenta una excusa on localitzar geogràficament uns fets que podrien succeir al mateix Oest americà, a la Revolució francesa, o a la més rabiosa actualitat: la confrontació de dos móns. Wyler no justifica cap dels dos i més aviat es preocupa per mostrar les necessitats i les motivacions de cadascun d’ells.Cuatro artículos sobre Habitatges a la Plaça Europa: - Grans horitzons / Cristina Arribas Sánchez - Austeritat i cost ajustat / Jordi Olivés Salvadó - De 3 en 3 / José Miguel Roldán Andrade; Mercè Berenguè Iglesias - Procés d’execució d’obra i materials / Joan Rovira Durá

Effect of different CO2 concentrations on biomass, pigment content, and lipid production of the marine diatom Thalassiosira pseudonana

The marine diatom Thalassiosira pseudonana grown under air (0.04% CO2) and 1 and 5% CO2 concentrations was evaluated to determine its potential for CO2 mitigation coupled with biodiesel production. Results indicated that the diatom cultures grown at 1 and 5% CO2 showed higher growth rates (1.14 and 1.29 div day−1, respectively) and biomass productivities (44 and 48 mgAFDWL−1 day−1) than air grown cultures (with 1.13 div day−1 and 26 mgAFDWL−1 day−1). The increase of CO2 resulted in higher cell volume and pigment content per cell of T. pseudonana. Interestingly, lipid content doubled when air was enriched with 1–5% CO2. Moreover, the analysis of the fatty acid composition of T. pseudonana revealed the predominance of monounsaturated acids (palmitoleic-16:1 and oleic-18:1) and a decrease of the saturated myristic acid-14:0 and polyunsaturated fatty acids under high CO2 levels. These results suggested that T. pseudonana seems to be an ideal candidate for biodiesel production using flue gas

The ground based plan A plan for research in astronomy and planetary science by ground based techniques

SIGLEAvailable from British Library Document Supply Centre- DSC:1769.7F(INIS-GB--186)(microfiche) / BLDSC - British Library Document Supply CentreGBUnited Kingdo

Cheaper membrane materials for microalgae dewatering

The final publication is available at Springer via http://10.1007/s10853-014-8408-8Among different strategies to reduce costs in microalgae dewatering process via cross-flow filtration, the one related to membrane material was investigated in order to be decreased. Several materials were tested, starting with the ones commonly used in membrane technology [ceramic, polysulfone (PSf) and polyacrylonitrile (PAN)] to the ones generally employed in packaging industry [acrylonitrile butadiene styrene (ABS), glycol-modified polyethylene terephthalate (PETG) and polylactic acid (PLA)], the latter being considerably cheaper. Experiments carried out showed promising results in terms of permeabilities for PSf-Pluronic® F127 blended membranes and PAN membranes (11 ± 1 L/h/m2/bar and 22 ± 1 L/h/m 2/bar, respectively, instead of 2 ± 2 L/h/m2/bar of PSf membranes), but with high related costs. PLA membranes showed good mechanical properties, biodegradability and price, but low permeability values (5 ± 1 L/h/m2/bar). PETG membranes showed attractive results in terms of costs and permeability, but poor mechanical properties. The polymer that offered the best results was the ABS that reached membrane permeabilities of 19 ± 1 L/h/m2/bar, maintaining good mechanical properties while filtering the microalgae Phaeodactylum tricornutum Bohlin. Thus, a novel functionality was found for these not so common polymers in microalgae dewatering. This indicates that use of these materials could also be considered in other aqueous micro/ultrafiltration applications. In addition, the biodegradable PLA polymer introduces a new concept of cheap and environmental friendly membrane in this application. © 2014 Springer Science+Business Media New York.Peer Reviewe

Nutritional and risk assessment of the consumption of pangasius

Panga; Avaluació del risc; ArsènicPanga; Evaluación del riesgo; ArsénicoPanga; Risk assessment; ArsenicEl consum de panga, un peix blanc de riu produït en piscifactories al sud-est asiàtic, ha estat controvertit per l’aportació nutricional, el contingut excessiu de contaminants i la sostenibilitat ambiental. Aquest document recull la opinió d’aquest Comitè Assessor sobre els temes de controvèrsia relacionats amb la seguretat d’aquest consumEl consumo de panga, un pescado blanco de río producido en piscifactorías en el sureste asiático, ha sido controvertido por el aporte nutricional, el contenido excesivo de contaminantes y la sostenibilidad ambiental. Este documento recoge la opinión de este Comité Asesor sobre los temas de controversia relacionados con la seguridad de este consumo.The consumption of panga, a white river fish produced in fish farms in Southeast Asia, has been controversial due to the nutrition, excessive content of pollutants and environmental sustainability. This document collects the opinion of this Advisory Committee on the issues of controversy related to the safety of this consumption

Nutritional and risk assessment of the consumption of pangasius

Panga; Avaluació del risc; ArsènicPanga; Evaluación del riesgo; ArsénicoPanga; Risk assessment; ArsenicEl consum de panga, un peix blanc de riu produït en piscifactories al sud-est asiàtic, ha estat controvertit per l’aportació nutricional, el contingut excessiu de contaminants i la sostenibilitat ambiental. Aquest document recull la opinió d’aquest Comitè Assessor sobre els temes de controvèrsia relacionats amb la seguretat d’aquest consumEl consumo de panga, un pescado blanco de río producido en piscifactorías en el sureste asiático, ha sido controvertido por el aporte nutricional, el contenido excesivo de contaminantes y la sostenibilidad ambiental. Este documento recoge la opinión de este Comité Asesor sobre los temas de controversia relacionados con la seguridad de este consumo.The consumption of panga, a white river fish produced in fish farms in Southeast Asia, has been controversial due to the nutrition, excessive content of pollutants and environmental sustainability. This document collects the opinion of this Advisory Committee on the issues of controversy related to the safety of this consumption