http://hdl.handle.net/10174/50 Mon, 06 Apr 2026 14:51:17 GMT 2026-04-06T14:51:17Z http://hdl.handle.net/10174/38212 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. Tue, 28 May 2024 23:00:00 GMT http://hdl.handle.net/10174/38212 2024-05-28T23:00:00Z http://hdl.handle.net/10174/38210 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. Wed, 29 May 2024 23:00:00 GMT http://hdl.handle.net/10174/38210 2024-05-29T23:00:00Z http://hdl.handle.net/10174/36782 Title: Quercetin-1,2,3-Triazole Hybrids as Multifunctional Anti-Alzheimer's Agents Authors: Carreiro, Elisabete; Costa, Ana; Antunes, Célia; Burke, AJ; Pinto, F.; Ernesto, S.; Rodrigues, B. Abstract: The number of patients with Alzheimer’s disease (AD) continues to rise and, despite the efforts of researchers, there are still no effective treatments for this multifaceted disease. The main objective of this work was the search for multifunctional and more effective anti-Alzheimer agents. Herein, we report the evaluation of a library of quercetin-1,2,3-triazole hybrids (I–IV) in antioxidant, hydrogen peroxide-induced oxidative stress protection, and cholinesterases (AChE and BuChE) inhibitory activities. Hybrids IIf and IVa-d showed potent in vitro inhibitory activity on eqBuChE (IC50 values between 11.2 and 65.7 µM). Hybrid IIf, the best inhibitor, was stronger than galantamine, displaying an IC50 value of 11.2 µM for eqBuChE, and is also a competitive inhibitor. Moreover, toxicity evaluation for the most promising hybrids was performed using the Artemia salina toxicity assay, showing low toxicity. Hybrids IIf, IVb, and IVd did not affect viability at 12.5 µM and also displayed a protective effect against oxidative stress induced by hydrogen peroxide in cell damage in MCF-7 cells. Hybrids IIf, IVb, and IVd act as multifunctional ligands in AD pathologies. Thu, 09 Nov 2023 00:00:00 GMT http://hdl.handle.net/10174/36782 2023-11-09T00:00:00Z http://hdl.handle.net/10174/36781 Title: Continuous Flow Enantioselective Processes Catalysed by Cinchona Alkaloid Derivatives Authors: Carreiro, Elisabete; Burke, A.J.; Hermann, G.J.; Federsel, H.-J. Abstract: Without a doubt, asymmetric catalysis has been significantly enriched by the introduction of cinchona alkaloid derivatives. Moreover, such methods have been further enabled when used in conjunction with continuous flow systems. Besides being used in flow chemistry as organocatalysts, they also have been used as ligands or modifiers of metal catalysts. This has generally been accomplished via their immobilization on heterogeneous supports and incorporation into catalysis-enabling reactors or similar systems. In this minireview we look at the impact that cinchona-based catalysts and analogues have had on the field of continuous flow-chemistry during the last two decades or so. Tue, 15 Aug 2023 23:00:00 GMT http://hdl.handle.net/10174/36781 2023-08-15T23:00:00Z