7 research outputs found

    Phytoremediation of highly contaminated mining soils by Jatropha curcas L. and production of catalytic carbons from the generated biomass

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    This paper deals with the removal of heavy metals from marginal soil mixtures from the Cobre Las Cruces and Aznalcóllar mining areas containing high concentrations of metals (Cr, Fe, Ni, Cu, Zn, Cd, Hg, Pb and As) by means of phytoremediation using Jatropha curcas L., and the subsequent production of biocatalysts from the plant biomass. First, J. curcas L. was sowed in eight mixtures of these mining soils to study its adaption to these high-contaminated soils and its growth during 60 days in a greenhouse under conditions simulating the South of Spain's spring climate. Later, the most suitable soil mixtures for plant growth were used for 120-day phytoremediation under the same conditions. Heavy metal concentration in soils, roots, stems and leaves were measured by ICP-OES at the beginning, at the middle and at the end of the phytoremediation period, thus calculating the translocation and bioaccumulation factors. J. curcas L. was found to absorb great amounts of Fe (> 3000 mg kg−1 plant) as well as notable amounts of Pb, Zn, Cu, Cr and Ni, and traces of As. Other metals with lower initial concentrations such as Cd, Hg and Sn were completely removed from soils. Finally, the plant biomass was subjected to pyrolysis to obtain catalytic biocarbons, assessing the optimal temperature for the pyrolytic process by means of thermogravimetric analysis and Raman spectroscopy

    Biodiesel production from waste cooking oil in an oscillatory flow reactor. Performance as a fuel on a TDI diesel engine

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    This paper describes the biodiesel production from waste cooking oil (50% (v/v) olive oil/sunflower oil) in an oscillatory flow reactor (OFR) in batch mode. We mainly focused on the characteristics of the biodiesel and its performance as a fuel. First at all, we verified that biodiesel yield in OFR was higher than in stirred tank reactor (STR) under the same experimental conditions, and that composition and properties of the resulting biofuel did not depend on reactor type. Besides, biodiesel production in OFR took half the time than in STR. Subsequently, we modify some OFR operational parameters to assess their influence on biodiesel yield. The most suitable conditions were found to be 6:1 methanol to waste cooking oil molar ratio, 0.67 Hz oscillation frequency and 30 min reaction time. Finally, the biofuel obtained was tested in a 2.0 TDI 140 hp EURO4 engine installed on an engine test bench. Specific fuel consumption, particle size distribution and concentration of exhaust gas sample pollutants and were analysed running with commercial diesel, 50% (v/v) diesel/biodiesel blend (B50) and biodiesel (B100) in order to ensure the viability of using this biofuel in vehicle engines.Fondos de la Unión Europea - LIFE 13-Bioseville ENV/111

    Production of Oxygenated Fuel Additives from Residual Glycerine Using Biocatalysts Obtained from Heavy-Metal-Contaminated Jatropha curcas L. Roots

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    This work aims to shed light on the use of two biochars, obtained from the pyrolysis at 550 C of heavy-metal-contaminated Jatropha curcas L. roots, as heterogeneous catalysts for glycerol esterification using residual glycerine. To do this, glycerine from biodiesel production was purified. In a first step, H3PO4 or H2SO4 was used to remove non-glycerol organic matter. The glycerol-rich phase was then extracted with ethanol or propanol, which increased the glycerol content from 43.2% to up to 100%. Subsequently, the esterification of both purified glycerine and commercial USP glycerine was assayed with acetic acid (AA) or with acetic anhydride (AH) at 9:1 molar ratio to glycerol using Amberlyst-15 as catalyst. Different reaction times (from 1.5 to 3 h) and temperatures (100–115 C when using AA and 80–135 C when using AH) were assessed. Results revealed that the most suitable conditions were 80 C and 1.5 h reaction time using AH, achieving 100% yield and selectivity towards triacetylglycerol (TAG) almost with both glycerines. Finally, the performance and reuse of the two heterogeneous biocatalysts was assessed. Under these conditions, one of the biocatalysts also achieved 100% TAG yield.VI Plan Propio de Investigación y Transferencia of University of Seville grant VIPPIT-2019-I.

    Propiedades de la cal en pasta obtenida a partir del tratamiento de fosfoyesos de la industria de fertilizantes

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    El proceso industrial de fabricación de ácido fosfórico tiene como materia prima principal la roca fosf orita, compue sta mayoritariamente por apatito (Ca 5 (PO 4 ) 3 OH); produciéndose el ácido fosfórico por un lado y por otro un subproducto formado principalmente por sulfato hidratado de calcio, denominado fosfoyeso. La producción de ácido fosfórico en Huelva (SO España) ha sido objeto de controversia por la formación de balsas de este subproducto, sin suficiente control, en las marismas de la desembocadura del río Tinto. Un grupo de investigadores liderados desde el Dpto. de Física de la Materia Condensada de la Universidad de Sevilla ha desarrollado un procedimiento sencillo y muy eficiente de obtención de portlandita, en forma de pasta de cal, como producto de la reacción química de u na disolución de fosfoyesos con una solución de sosa alcalina: CaSO 4 ·2H 2 O + 2NaOH Ca(OH) 2 + Na 2 SO 4 + 2H 2 O Como es previsible, la portlandita obtenida es susceptible de carbonatación, actuando como sumidero para el secuestro mineral de CO 2 . Esta metodolog ía tiene el potencial de reducir simultáneamente dos problemas ambientales: la gestión de los residuos industriales peligrosos; y las emisiones de gases de efecto invernadero. Este trabajo presenta la caracterización química, mineralógica, morfología y granulométrica del producto obtenido de cara su potencial utilización en aplicaciones relacionadas con el sector de la construcción, considerando inicialmente sus posibilidades como conglomerante y consolidant

    Production of Oxygenated Fuel Additives from Residual Glycerine Using Biocatalysts Obtained from Heavy-Metal-Contaminated <i>Jatropha curcas</i> L. Roots

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    This work aims to shed light on the use of two biochars, obtained from the pyrolysis at 550 &#176;C of heavy-metal-contaminated Jatropha curcas L. roots, as heterogeneous catalysts for glycerol esterification using residual glycerine. To do this, glycerine from biodiesel production was purified. In a first step, H3PO4 or H2SO4 was used to remove non-glycerol organic matter. The glycerol-rich phase was then extracted with ethanol or propanol, which increased the glycerol content from 43.2% to up to 100%. Subsequently, the esterification of both purified glycerine and commercial USP glycerine was assayed with acetic acid (AA) or with acetic anhydride (AH) at 9:1 molar ratio to glycerol using Amberlyst-15 as catalyst. Different reaction times (from 1.5 to 3 h) and temperatures (100&#8315;115 &#176;C when using AA and 80&#8315;135 &#176;C when using AH) were assessed. Results revealed that the most suitable conditions were 80 &#176;C and 1.5 h reaction time using AH, achieving 100% yield and selectivity towards triacetylglycerol (TAG) almost with both glycerines. Finally, the performance and reuse of the two heterogeneous biocatalysts was assessed. Under these conditions, one of the biocatalysts also achieved 100% TAG yield

    Cetane number prediction of waste cooking oil-derived biodiesel prior to transesterification reaction using near infrared spectroscopy

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    Fifty waste cooking oils (WCOs) were transesterified with methanol (1:8 WCO:methanol molar ratio) at 60 °C for 60 min using NaOH as catalyst (1% wt.). Fatty acid methyl ester (FAME) composition of the resulting biodiesels was analysed by gas chromatography, and near infrared (NIR) spectra of these biodiesels and those of the starting WCOs were acquired. Biodiesel cetane number was then calculated from both FAME composition and from biodiesel NIR spectra, this last technique using the former one as reference data. Because of transesterification does not modify fatty acid distribution of the starting WCO, and the similarity between biodiesel and WCO NIR spectra, biodiesel cetane number was successfully predicted from WCO NIR spectra, achieving RPD (ratio of performance to deviation) of 3.83. Therefore, biodiesel cetane number (and, as consequence, any other biodiesel property related to FAME composition) can be predicted by NIR spectroscopy before performing the transesterification reaction, which allows beforehand selecting the most suitable substrates for biodiesel production.Unión Europea - LIFE 13-Bioseville ENV/ES/111

    Proyecto Druidas. Manual práctico sobre Mediación Educativa

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    Se trata de un manual escrito por los miembros/as del Proyecto Educativo Druida, para acercar la mediación y los métodos de gestión de conflictos a los más pequeños, en su proceso educativo y que sirva de referente a educadores y educadoras que se enfrentan cada día a la necesidad de desarrollar la "cultura del acuerdo" ante las disrupciones en el aula.Foro Internacional de Mediadores Profesionales FIME
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