http://hdl.handle.net/10174/1120 2026-04-06T23:54:14Z 2026-04-06T23:54:14Z Timóteo, Inês Monginho Casnado, Isabel P.P. Pestana da Paixão Cansado, Isabel http://hdl.handle.net/10174/38212 2025-03-14T17:06:32Z 2024-05-28T23:00:00Z

Title: Use of biomass residues in MB removal from aqueous phase Authors: Timóteo, Inês Monginho; Casnado, Isabel P.P.; Pestana da Paixão Cansado, Isabel Abstract: Each day, abundant agricultural and agro-industrial wastes are generated to fulfil the growing population’s increasing demand for food Preliminary results concerning the valorization of biomass waste through its use for water treatment are presented in this work. The efficacy of biomass residues, such as coconut shells and cork residues, was tested in the removal of methylene blue (MB) from the aqueous phase. The study of MB adsorption was conducted using a batch-based approach, and the effects of pH, the initial concentration of MB, adsorbent granulometry, contact time and temperature were evaluated. The MB adsorption was more effective at a pH 7. Temperature seems to have no significant effect on MB adsorption on coconut shells but the rising temperature promotes an increase in the amount of MB adsorbed on cork residues. Adsorption isotherms were obtained at 298 K, after a contact time of 24 h. The adsorption performance of the natural adsorbents was significantly high in coconut shells, with a granulometry lower than 0.63 mm, revealing a maximum removal capacity of 143.7 mg of MB per gram. With cork, using the same experimental conditions, the maximum amount of MB adsorbed reaches 102 mg of MB per gram, but with cork, the granulometry seems less relevant. These results are very similar to those obtained with Imbondeiro, which were considered to be extremely promising [1]. The possibility of using agricultural wastes as adsorbents in water treatment is becoming of great importance. These wastes can successfully replace adsorbents, such as activated carbons, which are currently used in water treatment but have a relatively high cost.

2024-05-28T23:00:00Z Nouira, Asma Bekri Abbes, Imene Cansado, Isabel P.P. Mourão, Paulo A.M. Castanheiro, José E.F. http://hdl.handle.net/10174/38210 2025-03-14T17:04:15Z 2024-05-29T23:00:00Z

Title: Using Activated Carbon Adsorbents Obtained from Plastic Wastes from the Tunisian Beverage Industry Authors: Nouira, Asma; Bekri Abbes, Imene; Cansado, Isabel P.P.; Mourão, Paulo A.M.; Castanheiro, José E.F. Abstract: In this study, we investigated the preparation of char and activated carbon (AC) materials derived from water bottles and bottle waste collected at a waste collection point in Tunisia. The materials were synthesized using a rotary horizontal tubular furnace on a lab/pilot scale and through chemical activation. Characterization of the carbon materials was performed using nitrogen adsorption isotherms at 77K and SEM-EDX analysis. Furthermore, we examined the effectiveness of the ACs in removing the antibiot-ics 4-amino-N-(5-methyl-1,2-oxazol-3-yl)benzenesulfonamide (sulfamethoxa-zole-C10H11N3O3S) and 5-(3,4,5-trimethoxybenzyl)pyrimidine-2,4-diamine (trime-thoprim) from aqueous solutions. The results revealed a maximum adsorption capaci-ty of 108.17 mg g-1 (85.34%) for sulfamethoxazole and 98.11 mg g-1 (89.73%) for trime-thoprim on the PET-KOH-1:1-800°C sample. Additionally, we analyzed the adsorption kinetics, fitting the data to pseudo-first and -second-order models, and studied the equilibrium isotherms using the Langmuir and Freundlich equation models. These findings suggest significant potential for the application of ACs derived from plastic bottle waste in the treatment of wastewater containing antibiotics. Overall, our study highlights the feasibility of utilizing waste materials for the synthesis of valuable carbon-based adsorbents with promising adsorption capabilities. This research contributes to the ongoing efforts towards sustainable waste manage-ment and environmental remediation.

2024-05-29T23:00:00Z Teixeira, António P.S. Teixeira, Fátima C. Rangel, C. M. http://hdl.handle.net/10174/28911 2021-01-27T11:42:24Z 2020-11-01T00:00:00Z

Title: Novas Membranas Condutoras de Protões para Células de Combustível Authors: Teixeira, António P.S.; Teixeira, Fátima C.; Rangel, C. M. Editors: Gonçalves, H.; Romero, M. Abstract: As membranas de permuta protónica continuam a ser um material fundamental e um desafio chave no desenvolvimento das células de combustível. Neste trabalho foram preparadas, usando um método de casting, novas membranas de Nafion dopadas com 1 wt% de diferentes ácidos bisfosfónicos (BPs). As novas membranas foram avaliadas relativamente à sua capacidade de absorção de água (water uptake), por gravimetria, à sua capacidade de troca iónica (IEC), através da determinação da presença de grupos ionizáveis na membrana utilizando titulação potenciométrica ácido-base, e ao grau de hidratação. As novas membranas apresentaram valores superiores aos da membrana de Nafion utilizada como referência. A condutividade protónica das novas membranas foi avaliada por Espectroscopia de Impedância Eletroquímica (EIS), em diferentes condições de humidade relativa e de temperatura, tendo apresentado valores de condutividade protónica superiores às da membrana comercial de Nafion em todas as temperaturas e humidades relativas testadas.

2020-11-01T00:00:00Z Fernandes, Bruno Vicente, Henrique Ribeiro, Jorge Capita, António Analide, César Neves, José http://hdl.handle.net/10174/27676 2020-03-03T13:53:44Z 2019-01-01T00:00:00Z

Title: Fully Informed Vulnerable Road Users - Simpler, Maybe Better Authors: Fernandes, Bruno; Vicente, Henrique; Ribeiro, Jorge; Capita, António; Analide, César; Neves, José Editors: Indrawan-Santiago, Maria; Pardede, Eric; Salvadori, Ivan; Steinbauer, Matthias; Khalil, Ismail; Anderst-Kotsis, Gabriele Abstract: Vulnerable Road Users (VRUs) are all those with an increased vulnerability on the road, in particular non-motorised ones. Until now, the emphasis has been in politics more focused on drivers, vehicles and infrastructures. However, recent developments show a shift in other directions, with researchers now devoting efforts to improve VRUs' safety. Hence, this work focuses on pedestrian walking and crossing behaviour, attitudes, motivations and habits, being grounded on an approach to Knowledge Representation and Reasoning centred on logic programming, which establishes a formal logical inference engine that is complemented with an Artificial Neural Network line to computation.

2019-01-01T00:00:00Z