Resultados de investigación

The secondary sludge of wastewater treatment plants is an abundant and problematic bacterial biomass that accumulates nutrients from wastewater, mainly as proteins and carbohydrates. Recent studies have focused on energy recovery of this biomass by anaerobic digestion to produce biogas. However, fractional recovery of the sludge components could increase its value and provide the basis for a biorefinery based on this waste. Since ≈ 40-60% of the bacterial dry weight is protein, this biomass could be an important source of functional peptides or amino acids, and the carbohydrates could be used to produce bioplastics or biofuels. This study compares chemical, physical and biological hydrolysis methods and their sequential and assisted combinations to recover proteins and carbohydrates from sludge. Ultrasound-assisted alkaline treatment provided the highest protein solubilization yield (97.2%) with low degradation, resulting in peptide recovery yields of 75.1% with sizes from 70-215 kDa, 40% of essential amino acids and purity of 35.3% with NaOH 1M. The hydrothermal-alkaline combination almost completely solubilized the proteins but not the carbohydrates (77.4%) with high degradation (52.6%). The hydrothermal-acidic combination achieved high carbohydrate solubilization (94%) and recoveries of glucose (63.6%) and xylose (12.6%) but low protein recovery (43.7%) as small size peptides., Instituto de Procesos Sostenibles, Departamento de Ingeniería Química y Tecnología del Medio Ambiente, Ministerio de Ciencia, Innovación y Universidades, Consejeria de Educacion Junta de Castilla y Leon

Swine farming produces large quantities of nutrient-rich wastewater, which often contains metals such as Cu and Zn, used as feed additives for pigs. These metals must be removed from the wastewater before discharge but their retention in the biomass can limit its subsequent utilization. Photobioreactors are a very promising alternative for swine wastewater treatment, as the consortium of microalgae and bacteria growing symbiotically in these reactors allows high nutrient and metal removal efficiency at moderate costs. This work studies the mechanisms of removal of Cu(II) and Zn(II) by the two types of microorganisms growing in these photobioreactors. A microalga commonly used in wastewater treatment (Scenedesmus almeriensis) and an activated sludge were kept in contact with synthetic wastewater containing 100 mg/L of Cu and Zn. After 72 h, Scenedesmus almeriensis removed 43% of Cu and 45% of Zn, while activated sludge removed 78% of Cu and 96% of Zn. Single and sequential extractions of the biomasses using different extracting reagents revealed that biosorption on protonable groups is the dominant removal mechanisms. Mild reagents solubilized 69% of Cu and 94% of Zn from the microalgae and 76% of Cu and 93% of Zn from the activated sludge. Low metal concentrations in the oxidizable and residual fractions evidenced minimal bioaccumulation inside the cells. FTIR and ESEM-EDX analysis confirmed biosorption by ion exchange and complexation as the main metal remediation mechanisms. The weak bonds of the biosorbed Cu and Zn ions are beneficial for the valorization of biomass and the obtaining of safe bioproducts., Instituto de Procesos Sostenibles, Departamento de Química Analítica, Departamento de Ingeniería Química y Tecnología del Medio Ambiente, Ministerio de Ciencia, Innovación y Universidades, Consejeria de Educacion Junta de Castilla y Leon

Microalgae are a promising alternative to address wastewater treatment while converting wastewater nutrients into valuable protein-rich biomass, providing a dual-purpose solution. This study investigates protein recovery from microalgal biomass based on Scenedesmus almeriensis cultivated in swine wastewater using deep eutectic solvents (DESs) and their water mixtures. The behavior of two DESs (choline chloride:urea and choline chloride: glycerol at a 1:2 molar ratio) was evaluated with varying amounts of water. Both DESs outperformed water in protein extraction, and adding water to the DES:biomass mixture improved recoveries. The impact of the experimental factors was evaluated using a factorial design. The highest protein yield (16.8 %) was obtained with DES ChCl:2Urea with 81.6 % of water, by milling discs, a 12:1 DES:biomass ratio and extraction at 30 ◦C by 0.5 h. Despite moderate yields, this work underscores the potential of aqueous solutions of DESs as green solvents for protein recovery from microalgae., Instituto de Procesos Sostenibles, Departamento de Ingeniería Química y Tecnología del Medio Ambiente, Departamento de Química Analítica, Ministerio de Ciencia, Innovación y Universidades, Consejeria de Educacion Junta de Castilla y Leon, EU Feder Programme

The cultivation of microalgae in photobioreactors offers a sustainable approach for efficient treatment of nutrient-rich wastewater while producing biomass rich in valuable biocompounds that can be recovered. Aqueous two-phase systems (ATPSs) composed of the combination of two natural deep eutectic solvents (NADESs), betaine-levulinic acid (Bet:2LA) and choline chloride-urea (ChCl:2Urea), with di- and tripotassium phosphate salts, were evaluated as green extraction technologies for protein recovery from microalgal biomass cultivated in swine wastewater. The extraction capacity was compared with that of ATPSs formed by natural metabolites betaine or choline chloride and the phosphate salts. Binodal curves and tie-lines were experimentally determined for each system at 25 ºC to characterize the ATPS studied. Protein recovery yield (PRY) from the biomass was analyzed for the six ATPSs at three different extraction times at 25 ºC. The best compromise between PRY, selectivity relative to carbohydrate coextraction, and extraction time was achieved using the Bet:2LA NADES paired with K3PO4 after 30 min (PRY 16.4 %). This ATPS contains 50 % water, underscoring its environmentally friendly profile. These findings suggest the feasibility of NADES-based ATPS for efficient and fast protein extraction from wastewater-derived microalgal biomass in mild conditions.  , Instituto de Procesos Sostenibles, Departamento de Química Analítica, Departamento de Ingeniería Química y Tecnología del Medio Ambiente, Ministerio de Ciencia, Innovación y Universidades, Consejeria de Educacion Junta de Castilla y Leon, EU Feder Programme, MICIU/AEI/ 10.13039/501100011033

Raw data of Interviews used at the paper entitled: "RE-LIFE..."

Data corresponding to the publication "Static structure, microscopic dynamics and electronic properties of the Fe-Ni and Fe-Ni-S liquid alloys of geophysical interest. An ab initio molecular dynamics study.", submitted to Journal of Physics: Condensed Matter, Departamento de Física Teórica, Atómica u Óptica, GIR Propiedades Nanométricas de la Materia

Research data for the manuscript "Structure and motion of tritium and helium in the breeding-blanket-relevant liquid lithium-lead eutectic alloy: ab-initio molecular dynamics simulations." submitted to Journal of Physics: Condensed Matter., Departamento de Física Teórica, Atómica u Óptica, GIR Propiedades Nanométricas de la Materia

En la actualidad resulta imprescindible explorar nuevos sistemas de movilidad —junto con las narrativas que los sustentan— capaces de dar respuesta a los desafíos derivados del cambio climático. En este contexto, el presente trabajo se propone analizar los contradiscursos que promueven la bicicleta como medio de transporte sostenible y como solución ecológica frente a la crisis climática. El estudio identifica las principales metáforas conceptuales asociadas a la movilidad emergente contemporánea, tal y como se configuran en el discurso de activistas a favor del uso de la bicicleta en lengua española, inglesa y neerlandesa. El corpus, compuesto por 95 metáforas extraídas de la plataforma X (Twitter), se sometió a un análisis cualitativo. Partiendo de las estrategias previamente establecidas para resistirse a las metáforas dominantes (Gibbs & Siman, 2021; Van Poppel & Pilgram, 2023), se examina el funcionamiento de las metáforas de resistencia en el discurso activista. Los resultados evidencian que las metáforas de resistencia parcial reformulan los dominios fuente de mapeos institucionalizados (LA CIUDAD ES UN CUERPO, EL TRÁFICO ES UN SISTEMA CIRCULATORIO), presentando la movilidad motorizada como agente patógeno (p. ej., coágulo, droga, virus) que afecta negativamente al conjunto urbano, mientras que el ciclismo se perfila como elemento sanador (p. ej., infraestructuras ciclistas concebidas como tiritas o intervenciones quirúrgicas). Por su parte, las metáforas de resistencia completa revelan las limitaciones de la movilidad motorizada y proponen diseños alternativos mediante la introducción de nuevos dominios fuente (LAS CIUDADES SON ECOSISTEMAS, LAS CIUDADES SON CASAS). La contribución de estas metáforas al discurso sobre movilidad urbana oscila entre la oposición a la motonormatividad y la promoción del ciclismo como solución, favoreciendo nuevas formas de coexistencia urbana. Asimismo, la reconceptualización de la ciudad —que pasa de concebirse como un cuerpo mecanizado a entenderse como casa o ecosistema— pone de manifiesto un cambio funcional: de espacio para el desplazamiento a espacio para la vida., GIR Estilística Cognitiva y Praxis Literaria, Departamento de Filología Inglesa

Image files of Julia sets used in the manuscript "GPU-accelerated fractal compression dimension estimation" submitted to Fractal and Fractional., Departamento de Teoría de la Señal y Comunicaciones e Ingeniería Telemática

Research data corresponding to the paper "Static structure, microscopic dynamics and electronic properties of the Fe-Ni and Fe-Ni-S liquid alloys. An ab initio molecular dynamics study." submitted to Journal of Physics: Condensed Matter for publication., Departamento de Física Teórica, Atómica y Óptica, GIR Propiedades Nanométricas de la Materia