Maria Margarida Mateus
Instituto Superior Técnico
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Publication
Featured researches published by Maria Margarida Mateus.
Industrial Engineering and Management | 2015
dos Santos Rg; João C. Bordado; Maria Margarida Mateus
Cork wastes and by-products were used as raw materials to access sustainable biopolyols in a fast and clean manner. Contributing for the mitigation of a residue recorded as industrial residues in the European waste catalogue and hazardous waste list reducing, therefore, its environmental impact. Cork powder resulting from the cork industry as a waste and/or by-products with no commercial value was subjected to liquefaction in 2-ethyl hexanol/DEG in the presence of p-toluene sulfuric acid. Microwave radiation was used as the heating source. Pulsed microwaves from 150-300 W power were applied for 5-20 min. This alternative energy source was successfully applied leading to a high conversion of cork powder into liquid biopolyols. The efficiency of liquefaction increased with higher microwave power and shorter reaction time. This study evidenced that cork powder can be liquidized via microwave. ATR experiments indicated that microwave led to a more intense oxidized cleavage of the lignocellulosic material and more extensive liquefaction reaction when compared to the conventional procedure.
Data in Brief | 2016
Patrícia Ventura; João C. Bordado; Maria Margarida Mateus; Rui Galhano dos Santos
Herein, the data acquired regarding the preliminary and exploratory experiments conducted with potato peel as a biomass source for the direct thermochemical liquefaction is disclosed. The procedure was carried out in a 2-ethylhexanol/DEG solvent mixture at 160 °C in the presence of p-Toluenesulfonic acid. The adopted procedure afforded a bio-oil in high yield (up to 93%) after only 30 min. For longer reaction times, higher amounts of solid residues were obtained leading, consequently, to lower yields.
Journal of Polymers and The Environment | 2018
Rui Galhano dos Santos; Noemi Finez Acero; Sandro Matos; Ricardo Carvalho; Mário do Vale; Ana C. Marques; João C. Bordado; Maria Margarida Mateus
The use of petroleum-derived products should be avoided regarding the principles of green and sustainable chemistry. The work reported herein, is aimed at the liquefaction of pine shavings for the production of an environmentally-friendly polyol suitable to be used in the formulations of sprayable polyurethane foams. The biopolyols were obtained in high yield and were used to replace those derived from fossil sources, to produce more “greener” polyurethane foams and therefore, less dependent on petroleum sources, since the polyol component was substituted by products resulting from biomass liquefaction. The partial and fully exchange of the polyols was accomplished, and the results compared with a reference foam. The foams were afterward, chemical, physical, morphological, and mechanically characterized. The complete replacement of polyether polyol and polyol polyester has presented some similar characteristics as that used as a reference, validating that the path chosen for the development of more sustainable materials is on the right track for the contribution to a cleaner world.
Industrial Engineering and Management | 2017
Maria Margarida Mateus; Rui Galhano dos Santos
This short opinion manuscript aims to show a point of view of someone, who believes in biorefineries as an essential tool for a better future. However there are still many unsolved issues, in particular, the lack of alternatives to organic solvents often needed. Although, the biorefineries will be a tool that we can develop and leave as an inheritance for future generations.
Cellulose | 2017
Maria Margarida Mateus; Dinis Guerreiro; Olga Ferreira; João C. Bordado; Rui Galhano dos Santos
A clear, direct and rapid analysis of the preliminary results concerning the acid liquefaction of Eucalyptus globulus’ bark is herein presented. The results led to a methodology for the selective liquefaction of hemicellulose and amorphous cellulose. Liquefaction was conducted at various temperatures, as well as different reaction times. The process results are heuristically explained in view of the experiments of ATR-FTIR, hydroxyl number, and acid value. The procedure method allows reusing the wastes arising from the paper industry. Valuable products and chemical building blocks from lignocellulosic biomass, mostly based on cellulose can be thus accessed.
Data in Brief | 2016
Rui Galhano dos Santos; João C. Bordado; Maria Margarida Mateus
Herein, the integrated raw data regarding the 1H-NMR, experiments of Aesculetin, 4-Methylumbelliferone, and umbelliferone, in Acetone-d6 at 25 °C, are presented for further analysis and comparison purposes, for whom may be interested.
Industrial Crops and Products | 2015
Maria Margarida Mateus; Noemi Finez Acero; João C. Bordado; Rui Galhano dos Santos
Industrial Crops and Products | 2016
Rui Galhano dos Santos; Ricardo Carvalho; Elisabete Silva; João C. Bordado; Ana Cristina Cardoso; Maria do Rosário Costa; Maria Margarida Mateus
Fuel | 2016
Maria Margarida Mateus; João C. Bordado; Rui Galhano dos Santos
Journal of Cleaner Production | 2016
Rui Galhano dos Santos; João C. Bordado; Maria Margarida Mateus