5 documents found, page 1 of 1
Use of a rhodamine-based chelator in a microfluidic paper-based analytical devi...
Aguiar, Juliana I. S.; Ribeiro, Susana O.; Leite, Andreia; Rangel, Maria; Rangel, António O. S. S.; Mesquita, Raquel B. R.This work describes the development of a microfluidic paper-based analytical device (μPAD) for the determination of copper in fresh and marine waters. A functionalized rhodamine-based chelator was synthesized and used as a chromogenic reagent, forming a highly intense pink complex with the analyte. The aim was to create a paper device that offers optimal performance and provides in-situ, rapid and cost-effectiv...
Iron determination in natural waters using a synthesised 3-hydroxy-4-pyridione ...
Aguiar, Juliana I. S.; Ribeiro, Susana O.; Leite, Andreia; Rangel, Maria; Rangel, António O. S. S.; Mesquita, Raquel B. R.This work describes the development of an iron sensor based on a microfluidic paper-based technique, to attain iron quantification in natural waters. A new water-soluble naphthalene-3-hydroxy-4-pyridione ligand was used as a colour reagent, as it formed an orange complex with iron. As a newly described ligand, several chemical and physical parameters, namely, the sample and reagent volumes and reagent concentra...
Desulfurization process conciliating heterogeneous oxidation and liquid extract...
Ribeiro, Susana O.; Nogueira, Lucie S.; Gago, Sandra; Almeida, Pedro L.; Corvo, Marta C.; De Castro, Baltazar; Granadeiro, Carlos; Balula, SaleteThe present work presents a strategic oxidative desulfurization system able to efficiently operate under sustainable conditions, i.e. using an eco-friendly oxidant and without the need of extractive organic solvents. The catalytic performance of Eu(PW11O39)2@aptesSBA-15 was evaluated for the oxidative desulfurization of a multicomponent model diesel using a solvent-free or biphasic systems. The results reveal i...
Catalytic oxidative/extractive desulfurization of model and untreated diesel us...
Ribeiro, Susana O.; Julião, Diana; Cunha-Silva, Luís; Domingues, Valentina F.; Valença, Rita; Ribeiro, Jorge C.; Castro, Baltazar de; Balula, Salete S.The desulfurization efficiency of various hybrid zinc-substituted polyoxometalates ([PW11Zn(H2O)O39]5−, abbreviated as PW11Zn) was here investigated for the first time and optimized using sustainable systems conciliating successfully the liquid–liquid extraction and the oxidative catalytic process. Initially, the desulfurization studies were performed using a model diesel containing a mixture of the most refrac...
Production of ultra-deep sulfur-free diesels using a sustainable catalytic syst...
Granadeiro, Carlos M.; Ribeiro, Susana O.; Karmaoui, Mohamed; Valenca, Rita; Ribeiro, Jorge C.; de Castro, Baltazar; Cunha-Silva, LuisThe porous metal-organic framework UiO-66(Zr) obtained via non modulated synthesis, has revealed to be a notable heterogeneous catalyst, enabling extremely fast and very efficient desulfurization of a multicomponent model diesel and also a real diesel fuel.