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Aiming to develop a sustainable separation process reducing the water pollution, in this work Pinus pinaster (cluster pine) bark from a wood veneer industry was used for methylene blue and malachite green removal from aqueous systems. For single adsorption, the influence of time (up 8 h), adsorbent dose (2,5 - 5 - 10 g·L-1), temperature (25 ºC - 40 ºC - 60 ºC), pH (2 - 4 - 6) and particle size (0,1 mm - 0,5 mm, 0,5 mm - 1 mm and 1,6 mm - 2 mm) on adsorption was investigated. To study the initial concentration effect on binary adsorption, different concentrations (0 - 5 - 25 - 50 mg·L-1) were used at 25 ºC, natural pH and a dose of 5 g·L-1. High efficiency was obtained at pH = 4 (natural pH), dose of 5 g·L-1 and particle size of 0,5 - 1 mm. Adsorption percentages higher than 70 % were reached in less than one hour, with removal almost complete at equilibrium in single systems, without temperature influence. Methylene blue was slightly better adsorbed by bark. In binary systems, dyes exhibited competitive adsorption, decreasing their removal, especially increasing the initial concentration of the other dye. Dyes adsorption followed the pseudo-second order kinetic model, whereas the Langmuir isotherm explained adsorption equilibria in mono-component systems. High adsorption capacities (41,7 mg·g-1 for malachite green and 50,0 mg·g-1 for methylene blue) were obtained at 40 ºC and natural pH indicating that pine bark can be effectively used as biosorbent., Aiming to develop a sustainable separation process reducing the water pollution, in this work Pinus pinaster (cluster pine) bark from a wood veneer industry was used for methylene blue and malachite green removal from aqueous systems. For single adsorption, the influence of time (up 8 h), adsorbent dose (2,5 - 5 - 10 g·L-1), temperature (25 ºC - 40 ºC - 60 ºC), pH (2 - 4 - 6) and particle size (0,1 mm - 0,5 mm, 0,5 mm - 1 mm and 1,6 mm - 2 mm) on adsorption was investigated. To study the initial concentration effect on binary adsorption, different concentrations (0 - 5 - 25 - 50 mg·L-1) were used at 25 ºC, natural pH and a dose of 5 g·L-1. High efficiency was obtained at pH = 4 (natural pH), dose of 5 g·L-1 and particle size of 0,5 - 1 mm. Adsorption percentages higher than 70 % were reached in less than one hour, with removal almost complete at equilibrium in single systems, without temperature influence. Methylene blue was slightly better adsorbed by bark. In binary systems, dyes exhibited competitive adsorption, decreasing their removal, especially increasing the initial concentration of the other dye. Dyes adsorption followed the pseudo-second order kinetic model, whereas the Langmuir isotherm explained adsorption equilibria in mono-component systems. High adsorption capacities (41,7 mg·g-1 for malachite green and 50,0 mg·g-1 for methylene blue) were obtained at 40 ºC and natural pH indicating that pine bark can be effectively used as biosorbent

The significant increase in atmospheric CO2 concentration originated mainly from fossil fuels combustion has encouraged the development and improvement of CO2 separation operations to reduce emissions and control climate change and global warming. Therefore, this work is focused on the separation of CO2 from N2 in flue gas streams under post-combustion conditions by developing low-cost adsorbents. Six carbons were fabricated from biomass resources (olive stones and almond shells) to assess their influence on CO2 adsorption capacity: One carbonized and two KOH-activated carbons with carbon/KOH ratio of 1:2 and 1:4 (w/w) for each precursor. The carbons were characterized by field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), elemental analysis, nitrogen and carbon dioxide adsorption–desorption analysis, X-ray diffraction (XRD), Fourier transform infrared (FTIR), X-ray photoelectron spectroscopy (XPS) and point of zero charge determination. In addition, the equilibrium adsorption data of pure components for all adsorbents were measured at 0, 25 and 50 °C between 0 and 760 mmHg and CO2/N2 selectivity was determined. Activated carbons were found to have higher CO2 adsorption capacity but with a reduction in apparent selectivity. Dynamic binary adsorption simulations performed in a fixed-bed column demonstrated that the activated carbon produced from olive stones with a carbon/KOH ratio of 1:4 (w/w) can separate a mixture of 14 % CO2 and 86 % N2 at 25 and 50 °C with the highest selectivity, CO2 adsorption capacity, CO2 purity and N2 recovery factor. Reducing flow rate, the breakthrough time increased. Moreover, the breakthrough time was reduced by increasing the temperature from 25 to 50 °C owing to the exothermic nature of adsorption process.

The presence of valuable and hazardous metals in waste printed circuit boards, especially, motherboards, makes their recovery necessary as implies great economic and environmental advantages and develops urban mining processes. Hence, this research is focused on the selective leaching of Cu, Pb, and Sn as base metals using nitric acid and hydrochloric acid and Au, Ag, and Pd as precious metals using thiourea and sodium thiosulfate from waste motherboards’ PCBs in a sequential eco-friendly two-stage process. Previously, thiourea and sodium thiosulfate were used as leaching agents to investigate their applicability for the leaching of metals from PCBs in a single-stage process. Screening experimental design was applied to screen the variables affecting the leaching process in order to evaluate their impact on the recovery of metals and select the significant factors. The results demonstrated that base and precious metals can be leached appropriately in two consecutive stages compared to a single-stage process. Nitric acid was found to be a much more efficient agent to leach Cu and Pb in comparison with hydrochloric acid which was more suitable for the leaching of Sn. In the case of precious metals, higher amounts of Au were leached using thiourea, whereas sodium thiosulfate was able to leach more Pd. Roughly similar results were obtained for the leaching of Ag using these leaching agents. Nitric acid concentration, average particle size, temperature, and leaching time were found to be significant to maximize the leaching of Cu and Pb and minimize that for Au, Ag, and Pd in the first stage. Initial pH was the only variable influencing the second stage, in particular, Au leaching by thiourea

Due to the CO2 emissions and greenhouse effect, reducing its harmful impacts on climatic conditions is necessary. CO2 adsorption in a microporous carbon structure is one of the more effective separation techniques to avoid this type of emissions. In this work, one biochar (BC) and five activated carbons (ACs) were produced from Pinus radiata sawdust by chemical activation with potassium hydroxide (KOH) or zinc chloride (ZnCl2). Characterization was performed by scanning and transmission electron microscopy (SEM and TEM), surface area and pore size distribution by volumetric N2 and CO2 adsorption experiments using the Brunauer-Emmet-Teller (BET) and Barret-Joyner-Halenda (BJH) methods, respectively, X-ray diffraction (XRD), elemental analysis and X-ray photoelectron spectroscopy (XPS). The performance efficiency of the carbons was analyzed in terms of CO2 adsorption capacity at an absolute pressure range of 0–760 mmHg and at different temperatures (0, 25 and 50 ºC). The apparent and IAST selectivity of CO2 over N2 were determined and all carbons showed preferential sorption for CO2. Langmuir, Freundlich and Toth isotherms were employed to analyze pure CO2 and N2 adsorption data and the Toth isotherm gave the best fit. The carbon activated at 600ºC with KOH at a ratio of 1:4 w/w achieved the largest CO2 uptake (5.79 mmol/g at 0 °C and 750 mmHg) due to a combination between high microporosity (89 %) and surface area (2437 m2/g). This carbon also reached a relatively high selectivity

Carbon dioxide accumulation in the atmosphere and the presence of dyes in water resources are severe environmental issues to be solved. Consequently, in this work, adsorption is proposed as an efficient technique for both CO₂ capture from post-combustion process streams and dye removal from aqueous solutions. Pine sawdust, an eco-friendly and abundant residue from the wood industry, was used as adsorbent directly and after its conversion in biochar and activated carbons. The materials produced were thoroughly characterized and applied for CO₂ capture and for acid wood dye removal in batch and continuous mode analyzing the effect of various operational conditions. The results obtained demonstrated that pine sawdust-based carbons are promising alternatives to commercial activated carbons for the applications proposed.

In this work, the possibility of using un-treated pine (Pinus radiata) sawdust as biosorbent for the removal of three wood dyes (blue, red and black) from aqueous solutions was investigated. The BET surface area of the material was 1.55 ± 0.81 m2 g−1 using N2 at − 196 °C and 17.83 ± 0.032 m2 g−1 using CO2 at 0 °C. The point of zero charge was 4.8. In addition, the material was characterized before and after adsorption by surface analytical techniques. Assays were performed to analize the stability of wood dyes with time and pH and also to estimate the pKa values. Batch adsorption experiments were performed and the influence of experimental parameters such as contact time (up to equilibrium), stirring rate (100 and 210 rpm), adsorbent dose (2–10 g L−1), pH (2–9) and initial dye concentration (5 and 300 mg L−1) were studied. The optimum conditions were pH 2 and adsorbent dose of 6 g L−1 and the highest adsorption percentages achieved at 5 mg L−1 were: 100.0% for the blue, 99.7% for the black and 92.4% for the red. For 300 mg L−1 adsorption efficiency decreased to 85.6, 57.0 and 63.8% for the blue, black and red ones, respectively. Kinetic data were best fitted to the pseudo-second order model, suggesting a chemisorption process. Freundlich and Dubidin-Radushkevich were the best isotherm models. Regeneration study showed that un-treated pine sawdust could be reused efficiently for red dye removal at least in up to four repeated adsorption–desorption cycles using NaOH as desorption agent

Wastewater containing dyes are released into water bodies generating serious problems in human health and marine life. To contribute to the solution of this problem, a novel activated carbon was prepared from untreated pine (Pinus radiata) sawdust by dry chemical activation with ZnCl2 and was used for wood dye adsorption. The carbon was characterized by point of zero charge, N2 and CO2 adsorption isotherms, SEM-EDX, and FTIR. N2 and CO2 surface areas were 471.4 and 319.5 m2 g−1, respectively, with 91% of micropores. Wood dye adsorption was studied in function of pH (2–12), adsorbent dose (0.1–4 g L−1), time (up to 48 h for blue and red and 12 h for black), and initial concentration (5–500 mg L−1). The equilibrium data for the blue and black dyes were satisfactorily fitted to the Freundlich model while those for the red dye to the Langmuir model. Kinetic data were explained by the pseudo-second order (chemisorption process) and intraparticle diffusion models. At 5 mg L−1, a 100% removal efficiency was achieved at all pH for the blue dye, whereas for the red and black, natural pH (5.1) and pH = 2, respectively, led to the best removal efficiencies, 96 and 56%. Increasing concentration above 25 mg L−1 significantly reduced adsorption efficiency for blue and red dyes. For the black dye increasing the dose to 1 g L−1, the adsorption efficiency reached 82% at 25 mg L−1. High removal efficiencies were achieved for all dyes at 25 mg L−1 and 4 g L−1

Untreated Pinus radiata sawdust was investigated for the removal of Cu+2 ions from aqueous solutions. The biomass was characterized by Inductively Coupled Plasma-Mass (ICP-MS) spectrometry and by Scanning Electron Microscopy with an Energy Dispersive X-ray spectroscopy (SEM-EDX), X-Ray crystalline powder Diffraction (XRD) and Fourier Transform Infrared (FTIR) spectroscopy, before and after adsorption. The influence of contact time (up to equilibrium), adsorbent dose (1–50 g/L), initial metal ion concentration (5–300 mg/L) and pH (2–8) on copper sorption efficiency was studied through batch experiments. The results demonstrated that adsorption equilibrium is reached in less than 2 h and the best conditions (Cu+2 removal percentage, 93.4% and adsorption capacity, 0.82 mg/g) were achieved by increasing the adsorbent dose up to 5 g/L and the solution pH up to 7, and decreasing the initial metal concentration to 5 mg/L. The adsorption was optimized by means of a Doehlert experimental design analyzing the influence of adsorbent dose (5–15 g/L) and copper initial concentration (5–45 mg/L) on adsorption efficiency. Kinetic data were satisfactorily fitted to the second-order kinetic model. Intraparticle diffusion model demonstrated that different stages are involved in the adsorption process. Langmuir isotherms fitted satisfactorily the copper bioadsorption equilibrium data. Desorption studies achieved high efficiencies up to 94.5% and the possibility of sawdust regeneration was studied with four adsorption-desorption cycles. Thus, this study evidenced that sawdust is a promising efficient, renewable and economic adsorbent for metal removal and its use for that purpose constitutes an alternative for its management and valorization

[EN] The quality and freshness of fishery products has traditionally been determined by sensory evaluation methods, as well as by various analytical and instrumental techniques. However, all of them have several limitations. The first ones are subjective, as they depend on the personal judgment of a panel, while the second ones are generally invasive and destructive, requiring the selection of samples from the production batch and being unable to be applied to a complete production in an online way. Thus, a continuous effort is being made to find efficient methods and tools that allow the determination of quality and freshness in an objective, fast, reliable and non-destructive approach, in order to satisfy the expectations of consumers. In this regard, hyperspectral imaging (HSI) technology is one of the most promising in this field since, combined with multivariate analysis, it can result in a fast, non-invasive and non-destructive technique for the evaluation of fish quality indicators. However, most of the existing studies focus on processed fish, namely filets. In this work, correlation models using partial least squares regression (PLSR) have been developed to predict various quality indicators (quality index (QI) and colorimetric variables L, a and b of the CIELAB color space) in aquaculture whole turbot samples. Satisfactory results have been obtained for the prediction of QI using hyperspectral information collected from the dark side of turbots. This model was developed for 32 samples and 10 components and efficiently estimates the QI value of 9 samples of the external evaluation set, resulting in a normalized error of 1.0212 and a MSE of 8.7929., [ES] La calidad y frescura de los productos de la pesca se ha determinado tradicionalmente mediante métodos de evaluación sensorial, así como con diversas técnicas analíticas e instrumentales. Sin embargo, todos ellos adolecen de diversas limitaciones. Los primeros son subjetivos, pues dependen de la opinión personal de un panel, en tanto que los segundos son, por lo general, invasivos y destructivos, por lo que requieren la selección de muestras de un mismo lote y son incapaces de aplicarse a una producción completa de forma online. Así pues, existe una continua búsqueda de métodos y herramientas eficientes que permitan la determinación de la calidad y frescura de manera objetiva, rápida, fiable y que no lleven asociada la destrucción del alimento, con el fin de alcanzar las expectativas de los consumidores. En este contexto, la tecnología de imágenes hiperespectrales (HSI) es de las más prometedoras ya que, combinada con el análisis multivariable, puede resultar en una técnica rápida, no invasiva y no destructiva para la evaluación de indicadores de calidad del pescado. Sin embargo, la mayoría de las investigaciones existentes se centran únicamente en pescado procesado, principalmente filetes. En este trabajo se han elaborado modelos de correlación mediante regresión por mínimos cuadrados parciales (PLSR) para predecir varios indicadores de calidad (índice de calidad (QI) y variables colorimétricas L, a y b del espacio de color CIELAB) en muestras de rodaballo entero de acuicultura. Se han obtenido resultados satisfactorios para la predicción del QI a partir de la información hiperespectral recogida de la cara oscura. Este modelo, elaborado para 32 muestras y 10 componentes, logra estimar de forma eficaz el valor del QI de 9 muestras pertenecientes al conjunto externo de evaluación, obteniéndose un error normalizado de 1,0212 y un MSEE de 8,7929, [GA] A calidade e frescura dos produtos pesqueiros determináronse tradicionalmente mediante métodos de avaliación sensorial, así como diversas técnicas analíticas e instrumentais. Non obstante, todos sofren varias limitacións. Os primeiros son subxectivos, xa que dependen da opinión persoal dun panel, mentres que os segundos son xeralmente invasivos e destrutivos, polo que requiren a selección de mostras dun mesmo lote e son incapaces de ser aplicados á produción completa en liña. Así pois, existe unha busca continua de métodos e ferramentas eficientes que permitan determinar a calidade e a frescura de forma obxectiva, rápida, fiable e que non leve asociada a destrución do alimento, co fin de atender ás expectativas dos consumidores. Neste contexto, a tecnoloxía de imaxes hiperespectrais (HSI) é unha das máis prometedoras xa que, combinada coa análise multivariante, pode dar como resultado unha técnica rápida, non invasiva e non destrutiva para a avaliación dos indicadores de calidade do peixe. Non obstante, a maior parte das investigacións existentes céntranse unicamente no peixe procesado, principalmente filetes. Neste traballo desenvolvéronse modelos de correlación mediante regresión de mínimos cadrados parciais (PLSR) para predicir varios indicadores de calidade (índice de calidade (QI) e variables colorimétricas L, a e b do espazo cromático CIELAB) en mostras de rodaballo enteiro de acuicultura. Obtivéronse resultados satisfactorios para a predición do QI a partir da información hiperespectral recollida do lado escuro. Este modelo, desenvolvido para 32 mostras e 10 compoñentes, consegue estimar de forma eficiente o valor QI de 9 mostras pertencentes ao conxunto externo de avaliación, obténdose un erro normalizado de 1,0212 e un MSE de 8,7929

La industria forestal y agroalimentaria gallega en sus procesos de transformación generan gran cantidad de residuos de carácter lignocelulósico, siendo su principal destino el aprovechamiento energético. La naturaleza fenólica de estos residuos hace que surja la opción de vías alternativas o complementarias de valorización, como puede ser la obtención de antioxidantes naturales para su uso en la industria alimentaria, cosmética, etc., en sustitución de los antioxidantes sintéticos actualmente empleados. El objetivo es analizar el potencial antioxidante de los extractos obtenidos a partir de los residuos resultantes del procesado de la castaña en la industria alimentaria, la cáscara y el erizo, de residuos de madera de eucalipto de la industria maderera, residuos del procesado de la nuez como el pericarpio de nuez o la hoja del nogal y otros materiales como el involucro de avellana, madera de acacia o biomasa forestal residual procedente de la limpieza de los montes. Se analizará la influencia de la técnica de extracción, del agente extractor y de las condiciones de extracción, tales como temperatura, tiempo o relación sólido/líquido sobre las propiedades de los extractos (contenido en fenoles totales y capacidad antioxidante según los métodos FRAP, DPPH y ABTS) determinándose las condiciones que proporcionen altos rendimiento junto con extractos de elevada actividad antioxidante. También se realizarán estudios de la actividad antimicrobiana de extractos seleccionados. Finalmente, el perfil fenólico de los extractos se obtendrá mediante espectrometría de masas.

El presente proyecto tiene como objeto el diseño de una planta de producción de 10.000 toneladas al año de 2-propenal a partir de propileno con un mínimo de 95% de pureza. La producción se realizará en continuo 24 horas al día y durante 320 días al año. Para la obtención del 2-propenal mediante la oxidación parcial del propileno, la planta cuenta con un reactor catalítico (R-201), equipo que será diseñado por Andrea Estefanía Fernández Soto. Para aumentar la concentración del 2-propenal, también conocido como acroleína, el efluente del reactor se hace pasar por diversos equipos de separación. Primero se introduce en una columna quench (T-301), donde se enfría la corriente y se elimina la mayor parte de los subproductos ácidos acrílico y acético. Posteriormente, el gas es llevado a una columna de absorción (T-302) para eliminar los componentes no condensables y obtener una solución acuosa de acroleína, empleando agua como disolvente. Esta columna de absorción será diseñada por Alejandro José Jauregui Rodríguez. La solución acuosa se introduce en una columna de desorción (T-303) para obtener acroleína bruta, la cual es finalmente llevada a una columna de destilación (T-304) para enriquecer la corriente de producto en acroleína. La columna de destilación será diseñada por Andrea Paola Marques Cosme.

Highly N- and O-doped carbons were prepared from pine tannins by hydrothermal carbonisation (HTC) and subsequently applied as materials for supercapacitor electrodes. Pine tannins were transformed into carbon materials by using environment-friendly solvents (water or ammonia) without applying any activation or functionalisation post-treatment. Depending on the solution used for extracting tannins and on the HTC method, carbons with different physicochemical and electrochemical properties were obtained. The material prepared from the water-extracted tannin and subjected to HTC in ammonia displayed a porous texture composed of: (a) low ultramicroporosity and well-developed mesoporosity; (b) a hydrophilic surface with a high density of surface functionalities; and (c) a high nanotextural order. These features accounted for the excellent electrochemical performance of the resultant carbon electrode in terms of high rate capability up to 1 V s-1, high energy density up to ∼1500 mA g-1, low cell resistance and fast frequency response, making it a suitable material for practical supercapacitors.

Pinus pinaster bark, an abundant by-product from the timber industry, has been studied as a potential low-cost adsorbent for the removal of Congo red (CR) dye from wastewaters. Surface morphological and physico-chemical characteristics of pine bark were analysed using Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), determination of the point of zero charge (pHPZC) and elemental analysis. Assays were performed to determine the wavelength for the maximum absorbance and the stability with time of CR solutions depending on concentration and/or pH, which resulted to be a very signifcant parameter. Adsorption studies were conducted on batch mode to study the efect of contact time (till 7 days), pH (2–9), adsorbent dosage (1–10gL−1) and temperature (25–60°C). The bark adsorption capacity at equilibrium varied between 0.3 and 1.6mgg−1 and the equilibrium adsorption percentage between 23.4 and 100% depending on adsorbent dosage, temperature and pH at an initial CR concentration of 5mgL−1. Kinetic data for the removal of CR by pine bark were best ftted by the pseudo-second-order kinetic model. The equilibrium data ftted well with the Freundlich model. Thermodynamic analysis indicated that the adsorption process is exothermic and spontaneous

En la búsqueda de un crecimiento económico sostenible, las biorrefinerías, en las que se emplean diferentes tipos de biomasa para la producción de combustibles, productos químicos y materiales, han surgido como una potencial alternativa a las refinerías de petróleo. El reto es desarrollar biorrefinerías energéticamente eficientes, en las que se desarrollen productos ambientalmente aceptables a través de procesos con cero residuos, que sustituyan progresivamente a los actualmente producidos a partir del petróleo., In the search for sustainable economic growth, bio refineries, where different types of biomass are used for the production of fuels, chemicals and materials, have emerged as a potential alternative to oil refineries. The challenge is to develop energy-efficient bio refineries, in which environmentally acceptable products are created through processes with zero waste, which progressively replace those currently produced from petroleum.