2 resultados para RENEWABLE RESOURCES
em AMS Tesi di Laurea - Alm@DL - Università di Bologna
Resumo:
Biomass transformation into high-value chemicals has attracted attention according to the “green chemistry” principles. Low price and high availability make biomass one of the most interesting renewable resources as it provides the means to create sustainable alternatives to the oil-derived building blocks of the chemical industry In recent year, the need for alternative environmentally friendly routes to drive chemical reactions has in photocatalytic processes an interesting way to obtain valuable chemicals from various sources using the solar light as energy source. The purpose of this work was to use supported noble metal nanoparticles in the selective photo-oxidation of glucose through using visible light. Glucose was chosen as model molecule because it is the cheapest and the most common monosaccharide. Few studies about glucose photo oxidation have been conducted so far, and reaction mechanism is still not totally explained. The aim of this work was to systematically analyze and assess the impact of several parameters (eg. catalyst/substrate ratio, reaction time, effect of the solvent and light source) on the reaction pathway and to monitor the product distribution in order to draw a general reaction scheme for the photo oxidation of glucose under visible light. This study regards the reaction mechanism and the influence of several parameters, such as solvent, light power and substrate concentration. Furthermore, the work focuses on the influence of gold and silver nanoparticles and on the influence of metal loading. The glucose oxidation was monitored through the mass balance and the products selectivity. Reactions were evaluated in terms of glucose conversion, mass balance and selectivities towards arabinose and gluconic acid. In conclusion, this study is able to demonstrate that the photo oxidation of glucose under visible light is feasible; the full identification of the main products allows, for the first time, a comprehensive reaction mechanism scheme.
Resumo:
This project points out a brief overview of several concepts, as Renewable Energy Resources, Distributed Energy Resources, Distributed Generation, and describes the general architecture of an electrical microgrid, isolated or connected to the Medium Voltage Network. Moreover, the project focuses on a project carried out by GRECDH Department in collaboration with CITCEA Department, both belonging to Universitat Politécnica de Catalunya: it concerns isolated microgrids employing renewable energy resources in two communities in northern Peru. Several solutions found using optimization software regarding different generation systems (wind and photovoltaic) and different energy demand scenarios are commented and analyzed from an electrical point of view. Furthermore, there are some proposals to improve microgrid performances, in particular to increase voltage values for each load connected to the microgrid. The extra costs required by the proposed solutions are calculated and their effect on the total microgrid cost are taken into account; finally there are some considerations about the impact the project has on population and on people's daily life.