UB - Capítulos de livros
Permanent URI for this collection
Browse
Browsing UB - Capítulos de livros by Title
Now showing 1 - 10 of 16
Results Per Page
Sort Options
- Advances in the reduction of the costs inherent to fossil fuel biodesulfurization towards its potential industrial applicationsPublication . Paixão, Susana M.; Silva, Tiago; Arez, B. F.; Alves, LuísABSTRACT: The biodesulfurization (BDS) process consists of the use of microorganisms for the removal of sulfur from fossil fuels. Through BDS it is possible to treat most of the organosulfur compounds recalcitrant to the conventional hydrodesulfurization (HDS), the petroleum industry's solution, at mild operating conditions, without the need for molecular hydrogen or metal catalysts. This technique results in lower emissions, smaller residue production, and less energy consumption, which makes BDS an eco-friendly process that can complement HDS making it more efficient. BDS has been extensively studied and much is already known about the process. Clearly, BDS presents advantages as a complementary technique to HDS; however, its commercial use has been delayed by several limitations both upstream and downstream the process. This study will comprehensively review and discuss key issues, like reduction of the BDS costs, advances, and/or challenges for a competitive BDS towards its potential industrial application aiming ultra-low sulfur fuels.
- Advances in the reduction of the costs inherent to fossil fuel biodesulfurization towards its potential industrial applicationsPublication . Paixão, Susana M.; Silva, Tiago; Arez, B. F.; Alves, LuísABSTRACT: The biodesulfurization (BDS) process consists of the use of microorganisms for the removal of sulfur from fossil fuels. Through BDS it is possible to treat most of the organosulfur compounds recalcitrant to the conventional hydrodesulfurization (HDS), the petroleum industry's solution, at mild operating conditions, without the need for molecular hydrogen or metal catalysts. This technique results in lower emissions, smaller residue production, and less energy consumption, which makes BDS an eco-friendly process that can complement HDS making it more efficient. BDS has been extensively studied and much is already known about the process. Clearly, BDS presents advantages as a complementary technique to HDS; however, its commercial use has been delayed by several limitations both upstream and downstream the process. This study will comprehensively review and discuss key issues, like reduction of the BDS costs, advances, and/or challenges for a competitive BDS towards its potential industrial application aiming ultra-low sulfur fuels.
- Advances in the reduction of the costs inherent to fossil fuels’ biodesulfurization towards its potential industrial applicationPublication . Paixão, Susana M.; Arez, B. F.; Silva, Tiago; Alves, LuísBiodesulfurization (BDS) process consists on the use of microorganisms for the removal of sulfur from fossil fuels. Through BDS it is possible to treat most of the organosulfur compounds recalcitrant to the conventional hydrodesulfurization (HDS), the petroleum industry’s solution, at mild operating conditions, without the need for molecular hydrogen or metal catalysts. This technique results in lower emissions, smaller residue production and less energy consumption, which makes BDS an eco-friendly process that can complement HDS making it more efficient. BDS has been extensively studied and much is already known about the process. Clearly, BDS presents advantages as a complementary technique to HDS; however its commercial use has been delayed by several limitations both upstream and downstream the process. This study will comprehensively review and discuss key issues, like reduction of the BDS costs, advances and/or challenges for a competitive BDS towards its potential industrial application aiming ultra low sulfur fuels.
- Dark fermentative hydrogen production: from concepts to a sustainable productionPublication . Moura, Patrícia; Ortigueira, Joana; Valdez-Vazquez, Idania; Saratale, Ganesh D.; Saratale, Rijuta G.; Silva, Carla M.ABSTRACT: The use of renewable sources and environmentally friendly processes is considered a priority for the construction of a sustainable energy future. The harmful impact of fossil fuels and the fact that we are reaching a disrupting point regarding environmental damage require the rapid implementation of new energy systems and a substantial increase in the use of alternative, unconventional energy sources. Hydrogen (H2) is considered one of the most promising sources as a clean energy vector, because of its high energy density (120 MJ/kg) and carbon-free combustion (Argun and Kargi, 2011). Hydrogen is the simplest and most abundant element on earth; however, it barely exists in nature in its molecular state. Instead, it is almost always found as part of other compounds from which it should be separated, either by thermochemical processes or through biological conversion.
- Deconstruction of the hemicellulose fraction from lignocellulosic materials into simple sugarsPublication . Gírio, Francisco; Carvalheiro, Florbela; Duarte, Luís C.; Lukasik, Rafal M.Hemicelluloses hold a great promise for the production of added-value compounds in the biorefinery framework. Specifically, the xylan-rich hemicelluloses from hardwoods and agro-industrial residues present themselves as effective feedstock choices for the biotechnological production of xylitol. This paper reviews the various hemicellulose structures present in such materials and critically evaluates the available processing options to produce xylose-rich fermentable hydrolysates. Currently, acid-based processes still present the best trade-off between operation easiness and xylose yield and recovery. Nevertheless, concerns regarding the impact of the fractionation processes on the overall upgradability of all biomass fractions (namely, cellulose and specially lignin) may turn the route to other strategies. Specifically, the combined/sequential use of processes targeting hemicellulose dissolution and hydrolysis might hold great promise for the economical production of pentoses.
- Future perspectives of microalgae in the food industryPublication . Ferreira, Alice; Guerra, Inês; Costa, Margarida; Silva, Joana; Gouveia, LuisaABSTRACT: Microalgae have been consumed by humans for thousands of years. Research has shown that microalgae exhibit huge potential to meet the dietary needs of the growing population, generating great interest in these organisms. Thanks to their nutritional composition, mainly their high protein content, but also to the presence of bioactive compounds with functional properties that provide added health benefits, microalgae hold major opportunities for innovative and sustainable product development within the food industry. Furthermore, they possess compounds with stimulant properties that can be used to enhance agricultural yields, while providing an environmental benefit to sustainable agriculture. However, current microalgae exploitation for the food industry still presents some drawbacks, mainly because of the underdeveloped technologies and processes currently available for microalgae cultivation and processing. This chapter describes the use of microalgae as an ingredient in innovative food products with potential health benefits. It displays the research work done in a wide range of food products with incorporated microalgae, as well as some marketed microalgae-based food products commercially available today. Finally, the most promising future trends in microalgae food applications are highlighted.
- Indoor air quality in primary schoolsPublication . Freitas, Maria do Carmo; Canha, Nuno; Martinho, Maria; Almeida-Silva, Marina; Almeida, S. M.; Pegas, Priscilla; Alves, Célia; Pio, Casimiro; Trancoso, Maria Ascensão; Sousa, Rita; Mouro, Filomena; Contrira, Teresa
- Integration of polymeric-base wastes into petroleum refineriesPublication . Miranda, Miguel; Cabrita, Isabel; Alvarez, Nuno; Gulyurtlu, IbrahimThe continuous growth of world population along with incresing needs to improve life quality of societies and their dependence on fuel and other derived petroleum products suggest that the overall energy demand will increase significantly in the future. This chapter focuses the production of liquid fuels by pyrolysis applied to rubber tyre and diffetent plastic wastes as an option for integration in the refining process. The advantage is that pyrolysis of polymeric-base wastes tends to reverse the polymerization process used in the production of polymers at moderate conditions of temperature and pressure. The liquids obtained depend upon the polymeric blend. Products yields could lead to liquids similar to petroleum derived fuels as well as chemical feedstocks suitable to a wide range of industries. Considering that it is innivative the integration of polymeric-base wastes streams in petroleum refineries, a more detailed analysis on issues related to retrofitting will be presented.
- Ionic liquidsPublication . Lukasik, Rafal M.; Bogel-Lukasik, EwaIonic liquids (ILs) are a group of interesting compounds that have been known for more than a century, attracting major attention within the last two decades. ILs are often confused with molten salts. ILs are salts with the melting point arbitrarily determined to be below 100°C. They are composed of ions and, thus, each IL possesses unique properties that are the effect of a cation and an anion‘s nature. However, in general, ILs are characterized by a low melting point, high thermal and chemical stability, a large electrochemical window, great solvent power, nonflammability and a negligible vapor pressure. Density and viscosity, as well as many other properties, can easily be tuned as they are dependent on the chemical structure of the IL. Therefore, the ‘designer solvent‘ can be created for many applications, including biotransformation, chemical reactions (e.g., catalysis and hydrogenation), biorefinery concept, extraction and separation, and others.
- Mapping municipal solid waste to boost circular valorization practices in ŁódzkiePublication . Moura, Patrícia; Eusebio, Ana; Patinha, Pedro; Quental, Lídia; Lukasik, Rafal M.ABSTRACT: Geographic Information System (GIS) is a powerful instrument that can be used for the spatial representation of waste and by-product flows at various levels, allowing to improve municipal solid waste (MSW) management. The mapping obtained can be advantageously targeted to build a regional network of technological, economic, social and environmental linkages and to boost circular economy practices. In this work, the data on MSW produced in the Łódzkie region, Poland, during 2021 were used to generate a geolocalized database and an interactive web map, using ArcGIS software. The geodatabase and the map visualization were organized in three layers of information with increasing detail to foster a map-driven symbiosis between waste suppliers and waste recipients, paving the way for a more circular regional economy.