abstract
The biofuels have been at the forefront of global energy policies as their advantages can overcome the uncertainties of fossil fuels. Biodiesel has proven to be a very reliable fuel alternative to petrodiesel. It is a mixture of fatty acid alkyl esters obtained by the transesterification of vegetable oils and animal fat. As fuel, biodiesel is economically viable, socially responsible, technically compatible and environmentally friendly. The main challenge associated to its development concerns the choice of raw materials for its production. In third world countries, edible oils are more important for feeding people than for running cars. This thesis aims to produce / process biodiesel from resources endogenous of Timor-Leste and to measure/predict the thermodynamic properties of biodiesel, from those of alkyl esters. The synthesis of biodiesel from oils of Aleurites moluccana, Jatropha curcas and coffee waste were here studied. The thermodynamic properties such as density, viscosity, surface tension, volatility and speed of sound were also measured and estimated using predictive models available in the literature including some equations of state like CPA and soft-SAFT. Timor Leste is a country rich in natural resources, but the majority of the population still lives in poverty and deprivation of access to basic services and decent living conditions. The exploitation of oil and gas in the Timor Sea has filled only the Oil Fund. The country still lacks electricity and fuels that are crucial to materialize policies for poverty reduction. As a solution, the Timorese government has recently established the Strategic Development Plan of 20 years whose priorities include bringing the development of oil from the sea to the south coast of Timor-Leste and developing renewable energy sources. It is in this latter context that biodiesel should be considered. Its development in the country will be contextually an appropriate solution for electricity supply, job creation and especially combat against poverty and deprivation. To be used as fuel, however, biodiesel must possess thermodynamic properties consistent with those specified in the standards of ASTM D6751 (in USA) or EN 14214 (in Europe) to ensure proper ignition, atomization and combustion in diesel engines.
subject category
PROGRAMA DOUTORAL EM ENGENHARIA QUÍMICA (3º CICLO)
authors
Samuel Venâncio de Sousa Freitas
our authors
supervisors
João Manuel Costa Araújo Pereira Coutinho; Álvaro Lima
Groups