ESTGV - DA - Artigo em revista científica, indexada ao WoS/Scopus
Permanent URI for this collection
Browse
Recent Submissions
- Estudos preliminares de Adsorventes Lenhocelulósicos para a Remoção de CefalosporinasPublication . Gonçalves Oliveira Valente da Cruz-Lopes, Luísa Paula; Araújo, R.; Lopes, Ana Rita Valente da Cruz; Weber Macena, Morgana; Esteves, BrunoIntrodução: A Acacia dealbata foi explorada como biosorvente para remover cefalosporina de soluções aquosas. Este estudo procura demonstrar a viabilidade de utilizar materiais lenhocelulósicos de baixo custona remoção de poluentes, valorizando resíduos de outras indústrias e reduzindo o impacto ambiental associado. Objetivo: O objetivo pretendeu avaliar a capacidade dos resíduos de acácia em adsorver a cefalosporina, analisando o seu potencial de adsorção e os modelos cinéticos envolvidos, de forma a explorar o seu uso no tratamento de águas. Métodos: Esta revisão foi conduzida utilizando uma abordagem sistemática para identificar, analisar e sintetizar a literatura relevante sobre a presença e o impacto dos antibióticos cefalosporínicos em ambientes aquáticos. Paralelamente, foram realizados testes de adsorção utilizando soluções de cefalosporina com concentração de 15 mg L⁻¹, variando o tempo de agitação entre 10 e 120 minutos. A cinética de adsorção foi avaliada com base nos modelos de pseudo-primeira ordem, pseudo-segunda ordem, Elovich e difusão intrapartícula. A adsorção foi analisada através de espectrometria UV-Vis, onde se identificou um pico de absorção característico a 240 nm. Resultados: Os resultados indicaram que o modelo de pseudo-primeira ordem apresentou o coeficiente de determinação mais elevado (R² = 0,991), sugerindo que o mecanismo predominante é a adsorção física. Esta análise confirmou a capacidade da acácia em adsorver cefalosporinas, evidenciando o seu potencial como biosorvente. Conclusão: Este estudo sublinha a relevância dos biosorventes, como a Acacia dealbata, no tratamento de poluentes da indústria farmacêutica. A utilização de materiais sustentáveis oferece uma solução promissora para o tratamento de águas, abrindo caminho para futuras aplicações no campo da biossorção.
- Characterization of Lignocellulosic Byproducts from the Portuguese Forest: Valorization and Sustainable UsePublication . Macena, Morgana; Gonçalves Oliveira Valente da Cruz-Lopes, Luísa Paula; Grosche, Lucas; Santos-Vieira, Isabel; Esteves, Bruno; Pereira, HelenaThe increasing emphasis on environmental sustainability has placed biomass as a versatile and renewable resource, while the management and disposal of forest byproducts remain a significant challenge. This study explores the valorization of forest biomass residues derived from Pinus pinaster, Pinus pinea, and the invasive species Acacia dealbata, with a focus on their potential application as bioadsorbents. A comprehensive physicochemical characterization was conducted for different biomass fractions (leaves, needles, and branches of varying diameters). Leaves and needles contained higher amounts of extractives (from 7.7% in acacia leaves to 18.8% in maritime pine needles) and ash (3.4 and 4.2% in acacia leaves and stone pine needles, respectively), whereas branches contained more holocellulose (from 59.6% in P. pinea small branches to 79.2% in P. pinaster large branches). ATR-FTIR and pHpzc analyses indicated compositional and surface charge differences, with higher pHpzc values in A. dealbata relative to Pinus. TG analysis showed that acacia large branches degraded at a lower temperature (320 °C) compared to Pinus species (440–450 °C). Overall, the findings highlight the suitability of these underutilized forest byproducts as bioadsorbents, contributing to the advancement of circular economy practices.
- Kinetics and Isotherm Study of Ceftriaxone Removal Using Functionalized Biochar Combined with PhotocatalysisPublication . Cruz-Lopes, Luísa ; Araújo, Rodrigo ; Lopes, Ana Rita ; Moles, Samuel ; Romero-Sarria, Francisca ; Esteves, BrunoThe increasing presence of antibiotics such as cephalosporins in wastewater represents a significant environmental risk. These compounds are excreted in large quantities, and conventional wastewater treatment plants are often ineffective at their removal. Consequently, the development of more sustainable and efficient treatment technologies is essential. In this study, the removal of cephalosporins from aqueous solutions was evaluated through adsorption using pine bark biochar, photocatalysis with TiO2, and a combination of both processes. Kinetic experiments were conducted with cephalosporin solutions (15 mg/L), employing 150 mg/L of biochar, 100 mg/L TiO2, or their combination, under continuous stirring and/or UV-vis irradiation. Samples were collected at 0 and 120 min and analyzed via UV-vis spectrophotometry. Adsorption isotherms were established for initial cephalosporin concentrations ranging from 5 to 50 mg/L. The biochar alone achieved a removal efficiency of 94.2% after 120 min. Photocatalysis with TiO2 alone resulted in 75% removal, while the combined approach reached 95.9%, indicating a synergistic effect between adsorption and photodegradation mechanisms. Kinetic data fitted the pseudosecond-order model, and the Langmuir isotherm provided the best correlation, suggesting monolayer adsorption. These findings demonstrate that pine bark biochar, whether used independently or in combination with TiO2, constitutes an eco-friendly, effective, and low-cost alternative for the removal of antibiotics from wastewater, while simultaneously contributing to the valorization of forestry residues
- Valorization of Pinecones as Biosorbents for Environmental Remediation of Zn-Contaminated WastewatersPublication . Macena, Morgana; Gonçalves Oliveira Valente da Cruz-Lopes, Luísa Paula; Grosche, Lucas; Esteves, Bruno; Santos-Vieira, Isabel; Pereira, HelenaEmpty pinecones are a largely available byproduct of Pinus pinea L. nut production, mostly concentrated in the Mediterranean area; e.g., in Portugal, around 70,000 tons of pinecones are produced annually. One valorization line for residual biomass is its use as biosorbents for the removal of contaminants in effluents and water courses which are an increasing environmental problem. This study explores the biosorbent potential of pinecones to remove zinc ions from aqueous solutions. We analyzed the morphology and chemical composition of pinecones (9.4% extractives, 37.0% lignin, 68.6% holocellulose, 1.4% ash). The effect of pH and adsorbent dose on the adsorption process was studied, as were the sorption kinetics and isotherms. The pinecones showed good potential to remove Zn ions, with 96% removal at pH 7 and a maximum adsorption capacity of 7.92 mg g−1 . The process followed the Freundlich isotherm model, indicating a heterogeneous surface and multilayer adsorption, and the pseudo-second-order kinetic model, suggesting chemisorption as the dominant mechanism. The use of pinecones as bio-adsorbent is therefore a green and low-cost alternative for environmental remediation and biomass waste management.
- Enhancing Pinus pinaster Wood Durability Through Citric Acid ImpregnationPublication . Gonçalves Oliveira Valente da Cruz-Lopes, Luísa Paula; Mariana Sell; A. Lopes, Rogério; Esteves, BrunoCitric acid (CA), a naturally occurring compound in fruits, mainly citrus, has gained attention for its eco-friendly potential in wood modification. Through esterification, citric acid reacts with wood polymers to form bonds that improve adhesion, dimensional stability, and durability while reducing moisture absorption and susceptibility to decay. This study evaluated the efficacy of CA as an eco-friendly wood treatment. Wood samples were treated with solutions at varying concentrations (5%, 10%, and 15%) and assessed for dimensional stability, mechanical properties, biological resistance, and ecotoxicity. CA treatments significantly improved dimensional stability, with higher concentrations yielding greater weight percent gain (WPG) and anti-swelling efficiency (ASE). Biological tests demonstrated exceptional termite resistance, with no survival and minimal mass loss in treated samples at higher concentrations. Similarly, fungal resistance improved, as citric acid inhibited fungal growth. Ecotoxicity tests showed relatively low phytotoxicity, with some decrease in germination indices (GI) at higher CA concentrations. These findings highlight CA as a sustainable wood treatment for enhanced durability and biodegradation resistance in construction and outdoor applications.
- Enhanced Properties of Cryptomeria japonica (Thunb ex L.f.) D.Don from the Azores Through Heat-TreatmentPublication . Esteves, Bruno; Nunes, Lina; A. Lopes, Rogério; Gonçalves Oliveira Valente da Cruz-Lopes, Luísa PaulaThis study evaluates the chemical, physical, mechanical, and biological properties of untreated and heat-treated Cryptomeria japonica (Thunb ex L.f.) D.Don wood from the Azores, Portugal. Heat treatment was performed at 212 ◦C for 2 h following the Thermo-D class protocol. Chemical analysis revealed an increase in ethanol soluble extractives and lignin content after heat treatment, attributed to hemicellulose degradation and condensation reactions. Dimensional stability improved significantly, as indicated by reduced swelling coefficients and higher anti-swelling efficiency (ASE), particularly in the tangential direction. Heat-treated wood demonstrated reduced water absorption and swelling, enhancing its suitability for applications requiring dimensional stability. Mechanical tests showed a decrease in bending strength by 19.6% but an increase in the modulus of elasticity (MOE) by 49%, reflecting changes in the wood’s structural integrity. Surface analysis revealed significant color changes, with darkening, reddening, and yellowing, aligning with trends observed in other heat-treated woods. Biological durability tests indicated that both untreated and treated samples were susceptible to subterranean termite attack, although heat-treated wood exhibited a higher termite mortality rate, suggesting potential long-term advantages. This study highlights the impact of heat treatment on Cryptomeria japonica wood, emphasizing its potential for enhanced stability and durability in various applications.
- Lignocellulosic Byproducts as Bio-Adsorbents for Lead RemovalPublication . Macena, Morgana; Pereira Helena; Grosche, Lucas; Esteves, Bruno; Santos-Vieira, Isabel; Gonçalves Oliveira Valente da Cruz-Lopes, Luísa PaulaWater pollution by toxic metals, especially by lead ions, is a serious environmental concern due to these metals’ persistence, bioaccumulation, and toxicity. Aiming to reduce metal concentrations to non-toxic levels, this study analyzed the removal of lead from water through adsorption with bio-adsorbents. The adsorbent potential of the following four lignocellulosic byproducts were tested: walnut and chestnut shells, pine wood, and burnt pine wood. Removal rates of 97–99% were achieved at optimized conditions, i.e., at a pH of approximately 7, adsorbent dose of 4 g L−1, and 12 h of reaction. The BET specific surface area was between 1.74 and 4.85 m2 g−1. The pore size of the wood bio-adsorbent was 26.54 nm, and those of the remaining materials were between 5.40 and 7.33 nm. With R2 = 0.998–1.000, the kinetics fit the pseudo-second-order model better, suggesting that chemisorption is the dominant mechanism. Both Langmuir and Freundlich isothermal models fit the data well, with R2 = 0.946–0.999. It can be concluded that all the bio-adsorbents tested have the potential to efficiently remove lead ions from water.
- Carbon footprint calculator for the Portuguese textile and clothing industry: development, application and validationPublication . C. Duarte; Ferreira, José; Lopes Brás, Isabel Paula; Ferreira Silva, Maria Elisabete
- Sustainable Heat Production for Fossil Fuel Replacement—Life Cycle Assessment for Plant Biomass Renewable Energy SourcesPublication . Lopes Brás, Isabel Paula; Fabriccino, Massimiliano; Ferreira, José; Ferreira Silva, Maria Elisabete; Mignano, VincenzoThis study aims to assess the environmental impact of using wood-based biomass as a high-efficiency fuel alternative to fossil fuels for heat production. To achieve this, the life cycle of biomass transformation, utilization, and disposal was analyzed using the life cycle assessment (LCA) methodology with SimaPro 9.5.0.2 PhD software. The system boundaries included extraction, processing, transportation, combustion, and waste management, following a cradle-to-gate approach. A comparative analysis was conducted between natural gas, the most widely used conventional heating fuel, and two biomass-based fuels: wood pellets and wood chips. The results indicate that biomass utilization reduces greenhouse gas emissions (−19%) and fossil resource depletion (−16%) while providing environmental benefits across all assessed impact categories analyzed, except for land use (+96%). Biomass is also to be preferred for forest waste management, ease of supply, and energy independence. However, critical life cycle phases, such as raw material processing and transportation, were found to contribute significantly to human health and ecosystem well-being. To mitigate these effects, optimizing combustion efficiency, improving supply chain logistics, and promoting sustainable forestry practices are recommended. These findings highlight the potential of biomass as a viable renewable energy source and provide insights into strategies for minimizing its environmental footprint.
- Competitive Adsorption of Metal Ions by Lignocellulosic Materials: A Review of Applications, Mechanisms and Influencing FactorsPublication . Weber Macena, Morgana; Helena Pereira; Gonçalves Oliveira Valente da Cruz-Lopes, Luísa Paula; Lucas Grosche; Esteves, BrunoThe rapid expansion of industrial and agricultural activities in recent years has significantly contributed to water pollution leading to a decline in water quality and the need for effective treatment and reuse strategies. Metal contamination in water bodies poses severe environmental and health risks, making the development of cost-effective and sustainable remediation methods essential. Among the various treatment approaches, biosorption using biological adsorbents has emerged as a promising alternative due to its low cost and high efficiency. However, while the adsorption mechanisms of single metals are well understood, the competitive interactions between multiple metal ions during the sorption process remain less explored. In this review, we analyze the competitive biosorption of metals in multi-metallic wastewater systems. Key factors influencing metal removal, such as pH, contact time, biosorbent dosage, and initial metal concentration, are discussed, along with the intrinsic properties of biosorbents and metal ions that affect sorption efficiency. Additionally, we highlight recent studies on agroforestry byproducts as effective biosorbents for metal removal, showcasing their potential for sustainable water treatment. Heavy metals pose significant risks even at low concentrations, necessitating robust regulations and advanced treatment technologies; biomass byproducts, as cost-effective biosorbents, can be optimized through pre-treatment, activation, pH and temperature control, and particle size reduction, while effectively manage