Monica Alexandra Basto de Almeida e Silva
@tcd.ie
Postdoctoral Researcher/silvamn@tcd.iw
Trinity College Dublin
RESEARCH, TEACHING, or OTHER INTERESTS
Chemistry, Process Chemistry and Technology, General Engineering, Environmental Science
Scopus Publications
Scholar Citations
Scholar h-index
Scholar i10-index
Scopus Publications
S. P. Magalhães da Silva, Mónica A. Silva, and José M. Oliveira
Springer Science and Business Media LLC
Mónica A. Silva, Efres Belmonte-Reche, and Maria T. P. de Amorim
MDPI AG
Water contaminated with toxic dyes poses serious problems for human health and environmental ecosystems. Unfixed reactive dyes and their hydrolyzed form are soluble in water, thus, their removal is particularly challenging. Among the different methodologies, adsorption is probably the most common since it is easy to handle and has a low cost. Here, the removal by adsorption of hydrolyzed Reactive Black 5 (hydRB5) from a model wastewater through cellulose acetate/hematite membranes (CA/α-Fe2O3), designated as M1, M2 and M3, was performed. The pristine cellulose acetate membrane (CA) was designated as M0. Toward understanding the adsorption mechanism of hydRB5 on membranes, the rate of adsorption and maximum value of the adsorption capacity were evaluated using kinetic and isothermal studies, respectively. The results showed that the adsorption mechanism follows pseudo-first-order kinetics, and data are best fitted by the Langmuir isotherm method with a maximum adsorption capacity of 105.26 mg g−1 in pH~7. Furthermore, these membranes can be also regenerated by washing with NaOH and NaCl solutions, and the regeneration efficiency remains effective over five cycles. To complete the work, two statistical models were applied, an Analysis of Variance (ANOVA) and a Response Surface Methodology (RSM). The optimum value found is located in the usable region, and the experimental validation shows good agreement between the predicted optimum values and the experimental data. These composite membranes are also good candidates for the adsorption of other pollutants, even at industrial scale, due to their effective regeneration process and low production costs.
Mónica A. Silva, Efres Belmonte-Reche, and M.T. Pessoa de Amorim
Elsevier BV
M.A. Silva, C. Vieira Rocha, J. Gallo, H.P. Felgueiras, and M.T. Pessoa de Amorim
Elsevier BV
M. A. Silva, H. P. Felgueiras, and M. T. P. de Amorim
Springer Science and Business Media LLC
Mónica A. Silva, L. Hilliou, and M. T. Pessoa de Amorim
Springer Science and Business Media LLC
Mónica Silva, Isabel Martins, Filomena Barreiro, Madalena Dias, and Alírio E. Rodrigues
Informa UK Limited
ABSTRACT The synthesis of poly(urethane–urea) shells (PUU) using poly(ethylene glycols) of different molecular weights and methylene-bis(4-cyclohexylisocyanate) was performed for the microencapsulation of limonene, using a step-growth polymerization process. The obtained microcapsules were structurally characterized by dynamic light scattering, optical microscopy, scanning electron microscopy, Fourier transform infrared spectroscopy, and thermogravimetric analysis. The results showed that the core–shell microcapsules had spherical shape, a mean diameter in between 10 and 20 µm, and characteristic urethane-urea bonds. Furthermore, the molecular weight of polyol influences the entrapment efficiency, which ranged from 38 to 55%. The release data were analyzed by applying the Korsmeyer–Peppas model.
Mónica Silva, Isabel M. Martins, Maria F. Barreiro, Madalena M. Dias, and Alírio E. Rodrigues
Informa UK Limited
The majority of the commercially available microencapsulated fragrance systems with interest for textile applications are based on phenol–formaldehyde/melamine–formaldehyde resins. Recognized human health problems concerning formaldehyde emissions led to the use of poly(urethane–urea) (PUU) systems. In this work, fabrics were impregnated with PUU microcapsules containing limonene produced by interfacial polymerization. To aid the microcapsule impregnation, a specific binder was used followed by a drying and thermofixation process. The textiles were then subjected to abrasion and dry cleaning tests. Fragrance release was analysed for different binder to microcapsule ratios. SEM images of the impregnated samples indicate good adhesion of the microcapsules to the fabric fibres, but some capsule breakage was observed. Fragrance release tests were followed by GC–FID–HS and showed good resistance to abrasion tests with 30% of the initial limonene detected after 9000 abrasion cycles. A lower resistance was observed for the dry cleaning tests, although 20% of the limonene was still present after five dry cleaning cycles.
César A. Henriques, Fábio M. S. Rodrigues, Rui M. B. Carrilho, Mónica Silva, Auguste Fernandes, M. Filipa Ribeiro, and Mariette M. Pereira
Bentham Science Publishers Ltd.
Ana R. Freitas, Mónica Silva, M. Luísa Ramos, Licínia L. G. Justino, Sofia M. Fonseca, Madalina M. Barsan, Christopher M. A. Brett, M. Ramos Silva, and Hugh D. Burrows
Royal Society of Chemistry (RSC)
Having the HOMO of chromium(iii) tris-(8-hydroxyquinolinate) mainly on metal 3d orbitals and the LUMO on the ligand leads to increased electrochemical stability.
M. Silva, H. Ribeiro, I. Abreu, A. Cruz, and J. C. G. Esteves da Silva
Springer Science and Business Media LLC
Mónica Silva, Auguste Fernandes, Suse S. Bebiano, Mário J. F. Calvete, M. Filipa Ribeiro, Hugh D. Burrows, and Mariette M. Pereira
Royal Society of Chemistry (RSC)
Rationalisation of acidity and pore size influence on synthesis of hindered mesoarylporphyrins. Efficient, reusable and scalable alternative for one-pot synthesis in high yields.
Mário J. F. Calvete, Mónica Silva, Mariette M. Pereira, and Hugh D. Burrows
Royal Society of Chemistry (RSC)
This review considers several aspects (synthetic procedures and, particularly, catalytic applications) of the recent literature (since 2000) regarding the immobilisation of tetrapyrrolic macrocycles (namely porphyrins and phthalocyanines) in micro (NaY and NaX zeolites) and mesoporous inorganic supports (M41S family), and their employment in catalysis, predominantly in oxidation. Emphasis is placed on photocatalysis, which is of importance in the degradation of pesticides, herbicides, health care, personal care and domestic care products, all of which represent a current major environmental concern. Pertinent reflections are presented on the nature of both synthetic issues and catalytic evaluations, within the perspective of what has happened in the field so far, and what are the main guidelines and problems for future developments.
M. Silva, M.J.F. Calvete, N.P.F. Gonçalves, H.D. Burrows, M. Sarakha, A. Fernandes, M.F. Ribeiro, M.E. Azenha, and M.M. Pereira
Elsevier BV
M. Silva, M.E. Azenha, M.M. Pereira, H.D. Burrows, M. Sarakha, C. Forano, M.F. Ribeiro, and A. Fernandes
Elsevier BV
Monica Silva, Maria E. Azenha, Mariette M. Pereira, Hugh D. Burrows, Mohamed Sarakha, Maria F. Ribeiro, Auguste Fernandes, Paula Monsanto, and Fernando Castanheira
Walter de Gruyter GmbH
NaY zeolite and MCM-41 mesoporous molecular sieve were used as supports for immobilization of 5,10,15,20-tetrakis-(2-fluorophenyl)porphyrin (TFPP) using adsorption and ship-in-the-bottle routes involving the nitrobenzene method. The materials obtained were characterized by thermogravimetry/differential thermal analysis (TG/DTA), nitrogen adsorption, UV–vis absorption, diffuse reflectance (DRS), and luminescence spectroscopy. Although the porphyrin could easily be synthesized inside MCM-41 pores using the ship-in-the-bottle route, no significant porphyrin was formed in the smaller supercages of NaY zeolite, since the reaction stops at the dipyrrolylmethene intermediate (FDPM). Promising preliminary studies were made in the photodegradation of the pesticides, 2,3,5-trimethylphenol (TMP) and mecoprop (MCPP), using as catalyst TFPP encapsulated in mesoporous MCM-41 material. The 2-hydroxy-methyl-hydroquinone and 4-chloro-2-methylphenol were identified as the main degradation products of MCPP. The encapsulated system resulting from the TFPP template synthesis shows significantly enhanced performance when compared with adsorbed porphyrin in both supports.
M. Silva, C. Freire, B. de Castro, and J.L. Figueiredo
Elsevier BV
Mónica Silva, Ana Fernandes, Adélio Mendes, Célia M Manaia, and Olga C Nunes
Elsevier BV
M. Silva, R. Ferreira, C. Freire, B. de Castro, and J.L. Figueiredo
Elsevier
R Ferreira, M Silva, C Freire, B de Castro, and J.L Figueiredo
Elsevier BV
Joaquim C.G.Esteves Da Silva, Adélio A.S.C. Machado, and Mónica A.B.A. Silva
Elsevier BV