29 documents found, page 1 of 3
Silica-embedded metal oxide nanoparticles as epoxidation catalysts: batch and c...
Gomes, Diana M.; Yao, Xingyu; Neves, Patrícia; Antunes, Margarida M.; Pinna, Nicola; Russo, Patrícia A.; Valente, Anabela A.Catalytic epoxidation of olefins gives epoxide chemicals for several end-user products. With the technological advancements of these processes (especially for light olefins), which have importantly contributed to the epoxides market expansion, challenges remain in developing adequate heterogeneous catalysts for converting bulkier olefins, using simple catalyst synthesis procedures, and, on the other hand, study...
Biobased routes for the upgrading of α-angelica lactone to value added products
Antunes, Margarida M.; Silva, Andreia F.; Skrodczky, Kai; Fernandes, Auguste; Ribeiro, Filipa; Russo, Patricia A.; Pinna, Nicola; Pillinger, MartynBiomass derived compounds are important building blocks to produce value added bioproducts. These bioproducts can replace fossil fuel derivatives in a more sustainable approach, contributing to reduce CO2 emissions and a circular economy. More attention has been given to angelica lactone compounds due to their potential to be reduced to gamma-valerolactone (GVL) and other biobased products with several importan...
Chemical valorisation of biomass derived furanics and carboxylic acids over nio...
Antunes, Margarida M.; Cabanelas, Pedro S.; Skrodczky, Kai; Pinna, Nicola; Russo, Patrícia A.; Valente, Anabela A.Furfural is an industrial renewable platform chemical, which can be converted to useful furanics such as -angelica lactone, carboxylic acids such as levulinic acid and valeric acid, or to higher carbon content via condensation routes for producing drop-in fuel replacements and chemicals with diverse applications. These important conversion processes may be carried out in selective fashions, albeit require adeq...
Single-Step Formation of Metal Oxide Nanostructures Wrapped in Mesoporous Silic...
Skrodczky, Kai; Antunes, Margarida M.; Zhu, Qingjun; Valente, Anabela A.; Pinna, Nicola; Russo, Patrícia A.The integration of metal oxide nanomaterials with mesoporous silica is a promising approach to exploiting the advantages of both types of materials. Traditional synthesis methods typically require multiple steps. This work instead presents a fast, one-step, template-free method for the synthesis of metal oxides homogeneously dispersed within mesoporous silica, including oxides of W, Ti, Nb, Ta, Sn, and Mo. Thes...
Renewable bio-based routes to γ-valerolactone in the presence of hafnium nanocr...
Antunes, Margarida M.; Silva, Andreia F.; Fernandes, Auguste; Pillinger, Martyn; Ribeiro, Filipa; Valente, Anabela A.Different renewable bio-based routes leading to the versatile bioproduct c-valerolactone (GVL) were studied in integrated fashions, starting from furfural (Fur), a-angelica lactone (AnL) and levulinic acid (LA), in the presence of multifunctional hafnium-containing catalysts, in alcohol media. These routes involved acid and reduction reactions for which multifunctional catalysts were prepared via top-down strat...
Post-Synthesis Strategies to Prepare Mesostructured and Hierarchical Silicates ...
Gomes, Diana M.; Neves, Patrícia; Antunes, Margarida M.; Fernandes, António J. S.; Pillinger, Martyn; Valente, Anabela A.Olefin epoxidation is an important transformation for the chemical valorization of olefins, which may derive from renewable sources or domestic/industrial waste. Different post-synthesis strategies were employed to introduce molybdenum species into mesostructured and hierarchical micro-mesoporous catalysts of the type TUD-1 and BEA, respectively, to confer epoxidation activity for the conversion of relatively b...
Micro/mesoporous LTL derived materials for catalytic transfer hydrogenation and...
Antunes, Margarida M.; Silva, Andreia F.; Fernandes, Auguste; Ribeiro, Filipa; Neves, Patrícia; Pillinger, Martyn; Valente, Anabela A.The biomass-derived platform chemicals furfural and 5-(hydroxymethyl)furfural (HMF) may be converted to α-angelica lactone (AnL) and levulinic acid (LA). Presently, LA (synthesized from carbohydrates) has several multinational market players. Attractive biobased oxygenated fuel additives, solvents, etc., may be produced from AnL and LA via acid and reduction chemistry, namely alkyl levulinates and γ-valerolacto...
γ-Valerolactone synthesis from α-angelica lactone and levulinic acid over bioba...
Antunes, Margarida M.; Silva, Andreia F.; Fernandes, Auguste; Valente, Anabela A.The selective chemical conversion of biomass components to useful bioproducts may contribute to a renewable resource-based economy. The selective production of target bioproducts may be accomplished using heterogeneous catalysts operating under relatively moderate reaction conditions. In this work, carbohydrate biomass derived α-angelica lactone (AnL) and levulinic acid (LA) were converted to the versatile biop...
Catalytic Transfer Hydrogenation and Acid Reactions of Furfural and 5-(Hydroxym...
Antunes, Margarida M.; Silva, Andreia F.; Bernardino, Carolina D.; Fernandes, Auguste; Ribeiro, Filipa; Valente, Anabela A.Heterogeneous catalysis, which has served well the petrochemical industry, may valuably contribute towards a bio-based economy by sustainably enabling selective reactions to renewable chemicals. Carbohydrate-containing matter may be obtained from various widespread sources and selectively converted to furanic platform chemicals: furfural (Fur) and 5-(hydroxymethyl)furfural (Hmf). Valuable bioproducts may be obt...
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...