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The liquefaction process of cork based tree barks has led to an increase of interest due to its potential innovation in the lumber and wood industries. In this particular study the bark of Quercus cerris (Turkish oak) is used due to its appreciable amount of cork tissue, although of inferior quality when compared to the cork provided by other Quercus trees. This study aims to optimize alkaline catalysis liquefaction conditions, regarding several parameters. To better comprehend the possible chemical characteristics of the bark of Quercus cerris, a complete chemical analysis was performed. The liquefaction process was performed in a double-jacket reactor heated with oil, using glycerol and a mixture of glycerol/ethylene glycol as solvents, potassium hydroxide as a catalyst, and varying the temperature, liquefaction time and granulometry. Due to low liquefaction efficiency resulting from the first experimental procedures a study was made regarding different washing techniques after the filtration process using methanol and methanol/water. The chemical analysis stated that the bark of Quercus cerris is mostly composed by suberin (ca. 30%) and lignin (ca. 24%) as well as insolvent hemicelluloses in hot water (ca. 23%). On the liquefaction stage, the results that led to higher yields were: using a mixture of methanol/ethylene glycol as reagents and a time and temperature of 120 minutes and 200 ºC, respectively. It is concluded that using a granulometry of, {"references":["Kasaplıgil, B., \"Past and present oaks of Turkey\", Phytologia, vol. 49,1981, pp. 95-146.","Abi-Saleh, B. e Safi, S., \"Carte de la Végétation du Liban\"; Ecologia Mediterranea XIV (1/2), 1988, pp. 123-142.","Yaltırıc, F., \"Türkyie meşeleri teşis kılavuzu.\", Tarım Orman ve Köyişleri Bakanlığı Genel Müdürlüğü Yayınları. Yenilik Basimevi. Istambul. 1984.","Cotti, C., \"Molecular markers for the assessment of genetic variability in the threatened plant species.\", Tese de Doutoramento, Università degli studi di Bologna, 2008.","Berkel, A. e Bozkurt, Y., \"Untersuchungen über die makroskopischen und anatomischen holzmerkmale der wichtigsten Türkischen Eichenarten\", Istanbul Universitesi Orman Fakultesi Yayinlari, Kutulmus Matbaasi, Istanbul, 1961, 78.","La Marca, O., Uzielli, L. e Zanuttini, R., \"Possibilità di impegio del legname di cerro (Quercus cerris L.) in Italia. Indagini preliminari su alcuni popolamenti e prove sperimentali per l'industria dei compensati\", L'Italia Florestale e Montana 1, 1983, pp. 33-62.","Bartha, S., \"Cercatari Privind FActorii De Variatie A Caliatatii Lemnului De Cer Din Padurea Bobostea (Jud. Bihor)\", Rezumatul tezei de doctorat, Universitatea Transilvania Din Brasov, 2011.","Todaro, L., Zanuttini, R., Scopa, A., Moretti, N., \"Influence of combined hydro-thermal treatments on selected proprerties of Turkey oak (Quercus Cerris L.) wood\", Wood Science and Technology, vol. 46, 2012, pp. 563-578.","Mun, S., Gilmor, I. e Jordan, P., \"Effect of Organic Sulfonic Acids as Catalysts during Phenol Liquefaction of Pinus radiata Bark\", J. Ind. Eng. Chem., vol. 12, 2006, pp. 720-726.\n[10]\tAmorim. Diversidade e Aplicações. Amorim. (Online) 2015. http://www.amorim.com/a-cortica/diversidade-de-aplicacoes/.\n[11]\tAlma, H.M. e Bastiirk, M.A., \"Co-condensation of NaOH-catalysedliquefied wood wastes, phenol, and formaldehyde for the production of resol-type adhesives\", Ind. Eng. Chem. Res., 2001, pp. 5036–5039.\n[12]\tGandini, A., Neto, C.P. e Silvestre, A., \"Suberin: a promosing renewablere source for novel macromolecular materials\", Prog. Polym. Sci., vol. 31, 2006, pp. 878–892.\n[13]\tJin, Y.; Ruan, X.; Cheng, X.; Lü, Q., \"Liquefaction of lignin by polyethyleneglycol and glycerol.\", Bioresource Technology, 2011, pp. 3581–3583.\n[14]\tLin, L.; Yoshioka, M.; Yao; Y.; Shiraishi, N., \"Liquefaction of wood in the presence of phenolusing phosphoric acid as catalyst and the flow properties of the liquefied wood\", Journal of Applied Polymer Science, vol. 52, 1994, pp. 1629–1636.\n[15]\tMun, S., Hassan, E., \"Liquefaction of lignocellulosic biomass with mixtures of ethanol and small amounts of phenol in the presence of methanesulfonic acid catalyst\", J. Ind. Eng. Chem., vol. 10, 2004, pp. 722–727.\n[16]\tNasar, M.; Emam, A.; Sultan, M.; Hakim, A., \"Optimization and characterization of sugar-cane bagasse liquefaction process\", Indian J. Sci. Technol., 2010, pp. 207–212.\n[17]\tMin, N., Zhao, G, Alma, H.M., \"Polycondensation reaction and its mechanism during lignocellulosic liquefaction by an acid catalyst: a review\", Forestry Studies in China, vol. 13, 2011, pp. 71-79.\n[18]\tPereira, H., \"Chemical composition and variability of cork from Quercus suber L.\", Wood Sci. Technol., vol. 22(3), 1988, 211-218.\n[19]\tNeto, C.P., Seca, A., Fradinho, D., Coimbra, M.A., Domingues, F., Evtuguin, D., Silvestre, A., Cavaleiro, J.A.S., Chemical composition and structural features of the macromolecular components of Hibiscus cannabinus grown in Portugal. Industrial Crops and Products, vol.5(3): 1996, pp. 189-196.\n[20]\tBrowning, B.L., \"Methods in Wood Chemistry\", Vol. II. John Wiley& Sons, New York, USA, 1967, pp. 406-727.\n[21]\tMartins, J., Cruz Lopes, L., Esteves B., \"Otimização da liquefação da madeira de Pinus pinaster com poliálcoois\", Silva Lusitana. Nº Especial. Instituto Nacional de Investigação Agrária e Veterinária, vol. 21, 2013, pp. 177-185.\n[22]\tŞen, A., Miranda, I., Santos, S., Graça, J., Pereira, H., \"The chemical composition of cork and plhoem in the rhytidome of Quercus Cerris\", . Industrial Crops and Products, Vol.1 (2), 2010, pp. 417–422."]}

In order to fulfil European and Portuguese legal requirements, adequate alternatives to traditional municipal waste landfilling must be found namely concerning organic wastes and others susceptible of valorisation. According to the Portuguese Standard NP 4486:2008, refuse derived fuels (RDF) classification is based on three main parameters: lower heating value (considered as an economic parameter), chlorine content (considered as a technical parameter) and mercury content (considered as an environmental parameter). The purpose of this study was to characterize the rejected streams resulting from the mechanical treatment of unsorted municipal solid waste, from the plastic municipal selective collection and from the composting process, in order to evaluate their potential as RDF. To accomplish this purpose six sampling campaigns were performed. Chemical characterization comprised the proximate analysis – moisture content, volatile matter, ashes and fixed carbon, as well as trace elements. Physical characterization was also done. To evaluate their potential as RDF, the following parameters established in the Portuguese standard were also evaluated: heating value and chlorine content. As expected, results show that the refused stream from mechanical treatment is rather different from the selective collection rejected stream and from the rejected from the compost screening in terms of moisture, energetic matter and ashes, as well as heating value and chlorine. Preliminary data allows us to conclude that studied materials have a very interesting potential to be used as RDF. In fact, the rejected from selective collection and the one from composting have a heating value not very different from coal. Therefore, an important key factor may be the blending of these materials with others of higher heating values, after pre-processing, in order to get fuel pellets with good consistency, storage and handling characteristics and, therefore, combustion behavior. info:eu-repo/semantics/publishedVersion

Currently, the polyurethanes industry is dependent on fossil resources to obtain their basic raw materials (polyols and isocyanate), as these are obtained from petroleum products. The aim of this work was to use biopolyols from liquefied Pseudotsuga (Pseudotsuga menziesii) and Turkey oak (Quercus cerris) barks for the production of polyurethane foams and optimize the process. Liquefaction was done with glycerol catalyzed by KOH. Foams were produced following different formulations and using biopolyols from both barks. Subsequently, the foams were characterized according to their mechanical properties and the reaction of the foam formation was monitored by FTIR-ATR. The results show that it is possible to produce polyurethane foams using bio-based polyols and the liquefaction conditions are very important because they influence the characteristics of biopolyols and, consequently the characteristics of the foams. However, the process has to be further optimized so that it can obtain better quality foams info:eu-repo/semantics/publishedVersion

In order to fulfill legal requirements, adequate alternatives to traditional municipal waste landfilling must be found. The valorization of some residual streams from municipal solid waste (MSW) treatment plants are among them. The purpose of this study is to characterize the rejected streams resulting from the mechanical treatment of municipal solid waste and from the yellow waste container selective collection, in order to evaluate the potential of their valorization as Refuse Derived Fuel (RDF). To accomplish this purpose, two sampling campaigns were done. Physical characteristics, proximate analysis, heating value and chlorine content were determined. As expected, results show that the refused stream from mechanical treatment and from the selective collection are rather different in overall composition, water content, energetic matter and ashes, as well as heating value and chlorine, with the last showing higher calorific value and lower moisture, therefore superior energy recovery availability. Preliminary data allows us to conclude that studied materials have a very interesting potential to be used as RDF. info:eu-repo/semantics/publishedVersion

Dissertação de mestrado em Mecânica de Solos e Rochas, Departamento de Engenharia Civil da Faculdade de Ciências e Tecnologia