Departamento de Ingeniería Química, Ambiental y de los Materiales
URI permanente para esta comunidadhttps://hdl.handle.net/10953/42
En esta Comunidad se recogen los documentos generados por el Departamento de Ingeniería Química, Ambiental y de los Materiales y que cumplen los requisitos de Copyright para su difusión en acceso abierto.
Examinar
Examinando Departamento de Ingeniería Química, Ambiental y de los Materiales por Materia "6"
Mostrando 1 - 6 de 6
- Resultados por página
- Opciones de ordenación
Ítem Acid insoluble lignin material production by chemical activation of olive endocarps for an efficient furfural adsorption-removal from aqueous solutions(Elsevier, 2024-01-22) Cuevas, Manuel; Moya-López, Alberto José; Hodaifa, Gassan; Sánchez-Villasclaras, Sebastián; Mateo, SoledadThe present work describes a protocol of chemical activation, with acid catalyst, of olive endocarps to obtain acid insoluble lignin-rich materials with high capacities for the adsorption of furfural present in aqueous media. During biomass activation, factors such as acid concentration, reaction time and temperature, solid/liquid ratio and the presence of water extractives strongly affected both the surface characteristics of the treated bioadsorbents and their capacities for furfural retention (percentage increase close to 600% with respect to the crude biomass). Once a treated solid with good adsorbent properties was obtained, the optimal conditions for adsorption were found: stirring speed 80 rpm, temperature 303 K and adsorbent load 7.5 g solid/50 cm3. Kinetic study indicated the pseudo-second order model provided the best fit of the experimental data. At 303 K, the equilibrium adsorption capacities values ranged from 2.27 mg g−1 to 29.29 mg g−1, for initial furfural concentrations between 0.49 gdm−3 and 12.88 gdm−3. Freundlich model presented the best isotherm (R2 = 0.996 and SE = 4.7%) providing 𝐾𝐹 and 𝑛 values of 0.115 (mg g−1) (mg dm−3)−𝑛 and 0.610, respectively. Since physical interactions predominate in the adsorption of furfural on chemically activated olive endocarps, the furfural removal process could have occurred reversibly on the heterogeneous surface of the bioadsorbents.Ítem Bioconversion in batch bioreactor of olive-tree pruning biomass optimizing treatments for ethanol production(Elsevier, 2020-09-10) Fonseca, Bruno Guedes; Mateo, Soledad; Roberto, Inês; Sánchez-Villasclaras, Sebastián; Moya-López, Alberto JoséProcesses efficiency for second-generation ethanol production depends mainly on the type of lignocellulosic raw material. Therefore, the optimization (considering a central composite design) for each step involved in olive-tree pruning biomass valorization was studied: (1) alkaline pretreatment of the original feedstock, (2) diluted acid hydrolysis of pretreated solids and (3) fermentation of the hemicellulosic hydrolyzates for ethanol production by Scheffersomyces stipitis. The recommended alkaline pretreatment conditions were 30 min, 90 ◦C and 0.5% w/v NaOH, with losses of 88.3% of acetyl groups from starting biomass, but only 6.9% of D-xylose. Comparing both, in natura and previously treated acid hydrolyzates at the most effective conditions (2.0% w/v H2SO4 and 60 min) revealed more inhibitory effect for non-treated liquor, with 4.8, 2.1 and 1.6 times higher concentrations of acetic acid, furans and phenolic compounds, respectively. A significant improvement in ethanol production was observed in treated hemicellulose liquor (20.4 g dm-3, YP/S = 0.20 g g-1 and QP = 0.21 g dm-3 h-1). In contrast, the yeast could not satisfactorily ferment the reference hydrolyzate. Biomass pretreatment with alkali previously to dilute acid hydrolysis was a suitable strategy for olive-tree pruning biomass biotransformation, substantially decreasing the hydrolyzate toxicity, without requiring an additional detoxification step.Ítem Characterization of Cellulosic Pulps Isolated from Two Widespread AgriculturalWastes: Cotton and Sunflower Stalks(MDPI, 2024-06-04) la-Rubia, María Dolores; Jurado-Contreras, Sofía; Navas-Martos, Francisco; García-Ruiz, Ángeles; Morillas-Gutiérrez, Francisca; Moya-López, Alberto José; Mateo, Soledad; Rodríguez-Liébana, José AntonioGlobally, huge amounts of cotton and sunflower stalks are generated annually. These wastes are being underutilized since they are mostly burned in the fields. So, in this work, we proposed a three-step method consisting of acid pre-treatment, alkaline hydrolysis, and bleaching for the extraction of cellulose pulps. These pulps were characterized to assess their morpho-structural and thermal properties. The design of experiments and response surface methodology were used for the optimization of the acid pre-treatment in order to achieve maximum removal of non-cellulosic compounds and obtain pulps enriched in cellulose. For cotton stalks, optimal conditions were identified as a reaction time of 190 min, a reaction temperature of 96.2 ◦C, and an acid (nitric acid) concentration of 6.3%. For sunflower stalks, the optimized time, temperature, and acid concentration were 130 min, 73.8 ◦C, and 8.7%, respectively. The pulps obtained after bleaching contained more than 90% cellulose. However, special care must be taken during the process, especially in the acid pre-treatment, as it causes the solubilization of a great amount of material. The characterization revealed that the extraction process led to cellulose pulps with around 69–70% crystallinity and thermal stability in the range of 340–350 ◦C, ready to be used for their conversion into derivatives for industrial applications.Ítem Lignin from Plant-Based Agro-Industrial Biowastes: From Extraction to Sustainable Applications(2025-03-31) Mateo, Soledad; Fabbrizi, Giacomo; Moya-López, Alberto JoséLignin, the most abundant aromatic polymer in nature, plays a critical role in lignocellulosic biomasses by providing structural support. However, its presence complicates the industrial exploitation of these materials for biofuels, paper production and other high-value compounds. Annually, the industrial extraction of lignin reaches an estimated 225 million tons, yet only a fraction is recovered for reuse, with most incinerated as low-value fuel. The growing interest in lignin potential has sparked research into sustainable recovery methods from lignocellulosic agro-industrial wastes. This review examines the chemical, physical and physicochemical processes for isolating lignin, focusing on innovative, sustainable technologies that align with the principles of a circular economy. Key challenges include lignin structural complexity and heterogeneity, which hinder its efficient extraction and application. Nonetheless, its properties such as high thermal stability, biodegradability and abundant carbon content place lignin as a promising material for diverse industrial applications, including chemical synthesis and energy generation. A structured analysis of advancements in lignin extraction, characterization and valorization offers insights into transforming this undervalued by-product into a vital resource, reducing reliance on non-renewable materials while addressing environmental sustainability.Ítem Nanocellulose from Agricultural Wastes: Products and Applications—A Review(2021-09-06) Mateo, Soledad; Peinado-Serrano, Silvia; Morillas-Gutiérrez, Francisca; la-Rubia, María Dolores; Moya-López, Alberto JoséThe isolation of nanocellulose from different agricultural residues is becoming an important research field due to its versatile applications. This work collects different production processes, including conditioning steps, pretreatments, bleaching processes and finally purification for the production of nanocellulose in its main types of morphologies: cellulose nanofiber (CNF) and cellulose nanocrystal (CNC). This review highlights the importance of agricultural wastes in the production of nanocellulose in order to reduce environmental impact, use of fossil resources, guarantee sustainable economic growth and close the circle of resource use. Finally, the possible applications of the nanocellulose obtained as a new source of raw material in various industrial fields are discussed.Ítem Valorization of olive endocarp from olive oil and table olive processing as a low-cost bioadsorbent for the removal of furfural from aqueous solutions(Elsevier, 2021-11-18) Mateo, Soledad; Moya-López, Alberto José; Hodaifa, Gassan; Sánchez-Villasclaras, Sebastián; Cuevas, ManuelFurfural presence in fermentation culture media provokes an inhibition effect in yeast growth. In fact, is a key toxin in lignocellulosic hydrolyzates. This research work attempts to analyze the use of olive endocarp (OE) as adsorbent to remove furfural from aqueous solutions. The adsorption experimental sets studied the effect of particle size, agitation speed, adsorbent load, temperature, and initial furfural concentration. As results, higher adsorption percentages were observed when fragmented OE was smaller than 1.2 mm, agitation speed in the range 80–250 rpm, and the adsorbent load was 90 g OE/300 cm3 of furfural solution (1 g dm-3). The equilibrium adsorption capacities, qe, values were varied from 0.270 to 4.750 mg g-1 for initial furfural concentrations of 0.78 g dm-3 to 5.89 g dm-3. The adsorption data fit to pseudo-second order kinetic model showed good fit values (R2 ≥ 0.997, SE ≤ 5%). Dubinin-Radushkevich (DR) model was considered as the best fit (R2 = 0.999, SE =2.95%) for the different studied isotherms. An adsorption free energy value of 896 J mol-1 indicated a physical adsorption mechanism. Remarkable increases in furfural adsorption percentages have been achieved submitting natural olive endocarps to acid treatments.