21 documents found, page 1 of 3
Simultaneous sulfur and nitrogen removal from fuel combining activated porous M...
Silva, Dinis F.; Faria, Rui; Santos-Vieira, Isabel; Cunha-Silva, Luís; Granadeiro, Carlos M.; Balula, Salete S.The high costs associated with commercially available desulfurization technologies in the refinery industry urge for the development of novel, highly efficient and sustainable alternative processes. On the other hand, the presence of nitrogen compounds significantly decreases the efficiency of the process. Therefore, effective alternative methodologies capable to remove simultaneously sulfur and nitrogen compou...
MOF-Based Materials with Sensing Potential: Pyrrolidine-Fused Chlorin at UiO-66...
Queirós, Carla; Moscoso, Francisco G.; Almeida, José; Silva, Ana M. G.; Sousaraei, Ahmad; Cabanillas-González, Juan; Ribeiro Carrott, ManuelaAn efficient strategy to develop porous materials with potential for NO2 sensing was based in the preparation of a metal-organic framework (MOF), UiO-66(Hf), modified with a very small amount of meso-tetrakis(4-carboxyphenyl) N-methylpyrrolidine-fused chlorin (TCPC), TCPC@MOF. Chlorin’s incorporation into the UiO-66(Hf) framework was verified by several characterization methods and revealed that the as-synthesi...
Dichloro and dimethyl dioxomolybdenum(VI)-bipyridine complexes as catalysts for...
Julião, Diana; Gomes, Ana C.; Cunha-Silva, Luís; Pillinger, Martyn; Gonçalves, Isabel S.; Balula, Salete S.The complexes [MoO2Me2(2,2′-bipyridine)] (5), [MoO2X2(4,4′-dimethyl-2,2′-bipyridine)] (X = Cl (2), Me (6)), [MoO2Me2(4,4′-di‑tert‑butyl‑2,2′-bipyridine)] (7) and [MoO2X2(4,4′-dinonyl-2,2′-bipyridine)] (X = Cl (4), Me (8)) have been prepared and examined as catalysts in extractive and catalytic oxidative desulfurization (ECODS) of a simulated diesel fuel (3000 ppm S) containing dibenzothiophene, 4-methyldibenzot...
Impact of Ionic Liquid Structure and Loading on Gas Sorption and Permeation for...
Ortiz-Albo, Paloma; Ferreira, Tiago J.; Martins, Carla F.; Delgado Alves, Vitor; Esteves, Isabel A.A.C.; Cunha-Silva, Luís; Kumakiri, IzumiCarbon dioxide (CO2) capture has become of great importance for industrial processes due to the adverse environmental effects of gas emissions. Mixed matrix membranes (MMMs) have been studied as an alternative to traditional technologies, especially due to their potential to overcome the practical limitations of conventional polymeric and inorganic membranes. In this work, the effect of using different ionic li...
A silicododecamolybdate/pyridinium-tetrazole hybrid molecular salt as a catalys...
Nunes, Martinique S.; Neves, Patrícia; Gomes, Ana C.; Cunha-Silva, Luís; Lopes, André D.; Valente, Anabela A.; Pillinger, Martyn; Gonçalves, Isabel S.The hybrid polyoxometalate (POM) salt (Hptz)4[SiMo12O40]∙nH2O (1) (ptz = 5-(2-pyridyl)tetrazole) has been prepared, characterized by X-ray crystallography, and examined as a catalyst for the epoxidation of cis-cyclooctene (Cy) and bio-derived olefins, namely dl-limonene (Lim; a naturally occurring monoterpene found in the rinds of citrus fruits), methyl oleate and methyl linoleate (fatty acid methyl esters (FAM...
Cr-based MOF/IL composites as fillers in mixed matrix membranes for CO2 separation
Ferreira, Inês C.; Ferreira, Tiago J.; Barbosa, André D.S.; Castro, Baltazar; Ribeiro, Rui P.P.L.; Mota, José P.B.; Delgado Alves, VitorNew composite materials made of bromide-based ionic liquids (ILs) and metal–organic framework (MOF) MIL- 101(Cr) were produced using two different ILs. The powdered composites [PMIM][Br]@MIL-101(Cr) and [BMIM][Br]@MIL-101(Cr) were rigorously characterized, and it was confirmed that both ILs were incorporated into the MOF structure. Single-component CO2 and N2 adsorption–desorption isotherms for the pristine MIL...
A sustainable peroxophosphomolybdate/H2O2 system for the oxidative removal of o...
Julião, Diana; Gomes, Ana C.; Cunha-Silva, Luís; Valença, Rita; Ribeiro, Jorge C.; Pillinger, Martyn; de Castro, Baltazar; Gonçalves, Isabel S.Highly efficient, deep desulfurization of a multi-component model diesel containing benzothiophene (BT), dibenzothiophene (DBT) and 4,6-dimethyldibenzothiophene (4,6-DMDBT) has been achieved by using the peroxophosphomolybdate [(n-C4H9)4N]3{PO4[MoO(O2)2]4} (Q3PMo4) directly as catalyst, and aqueous H2O2 as oxidant. Q3PMo4 behaves as a heterogeneous catalyst in the complete oxidation of the various sulfur compou...
New hydrophilic 3-hydroxy-4-pyridinone chelators with ether-derived substituent...
Moniz, Tânia; Cunha-Silva, Luís; Mesquita, Raquel B.R.; Miranda, Joana L.A.; Silva, André M.N.; Silva, Ana M.G.; Rangel, António O.S.S.Three new hydrophilic 3-hydroxy-4-pyridinone chelators containing ether-derived substituents were prepared by a more sustainable synthetic protocol that involves the use of microwave heating and commercially available amines, allowing the successful production of highly water soluble chelators with improved reaction yields and reaction times. Compared with parent 3-hydroxy-4-pyridinone ligands, the new compound...
Mesoporous nanosilica-supported polyoxomolybdate as catalysts for sustainable d...
Mirante, Fátima; Gomes, Neide; Branco, Luis; Cunha-Silva, Luís; Almeida, Pedro L.; Pillinger, Martyn; Gago, S.; Granadeiro, Carlos; Balula, SaleteMesoporous silica nanoparticles (MSNs) strategically functionalized were used to immobilize a homogeneous polyoxomolybdate catalyst [PMo12O40](3-) (PMo12), active but unstable. The PMo12@TBA-MSN composite (where TBA refers to surface-tethered tributylammonium groups) conferred high stability to the polyoxomolybdate catalytic center and displayed an increase in efficiency for the oxidative desulfurization (ECODS...
A hydrogen-bonded assembly of cucurbit[6]uril and [MoO2Cl2(H2O)2] with catalyti...
Nogueira, Lucie S.; Antunes, Margarida M.; Gomes, Ana C.; Cunha-Silva, Luís; Pillinger, Martyn; Lopes, André D.; Valente, Anabela A.The reaction of the macrocyclic cavitand cucurbit[6]uril (CB[6]) and the diaqua complex [MoO2Cl2(H2O)2] in hydrochloric acid solution gave a water insoluble supramolecular compound with the general composition 2[MoO2Cl2(H2O)2]·CB[6]·xH2O·yHCl·z(CH3COCH3) (2). Single crystal X-ray diffraction (XRD) analysis revealed the presence of barrel-shape supramolecular entities, {CB[6]·10(H2O)}, aligned in layers which ar...