BIOFUELS: FROM HOPES TO REALITY

Kurzfassung

This paper combines the research for biofuels processing development with the vehicle conception to focus on realistic scenarios for biofuels to attend vehicle specifications and future green mobility. Actually, these are two important segments of fuels and biofuels context which should converge to a sustainable and realistic model. Recently, due to the climate changes versus fossil fuels use, and its consequences, the United Nations System addressed to the world a report on green economy indicating large investments properly. In synthesis, it seeks for a new world reality towards a sustainable economy with emphasis on bioresources, mainly on biofuels research and production. Historically, wood biomass has had an important role since the 18th century as a solid fuel used for heating and all types of society purposes. This was an indiscriminate use and it caused forest devastation and unsustainability in the North of Europe. In modern era, biomass assumed a challenging role due to the scientific development that supported the green revolution. In the last decades, agricultural markets were characterized by steady growth production, which induced price falling of agricultural products. After the seventies, world agricultural and land use suffered another challenging pressure to produce biofuels to replace fossil fuels. To support that, the 1961 Nobel Prize, Melvin Calvin made a fundamental scientific contribution to the understanding of the photosynthetic C3 and C4 plant mechanism of light absorption. In 1999, Melis and researchers from National Renewable Energy Laboratory in the USA discovered that the green algae, Chlamydomonas reinhartdtii could be forced to produce biohydrogen under Sulphur-free anaerobic conditions. This discovery is another fundamental step towards sustainable biohydrogen production in the future. Other biological processes are being developed at Duisburg-Essen University, in Germany, as well as, in other countries. In spite of biomass biodiversity and the renewable character of biofuels, they are still gaining space at regional level and impacting land use. However, no one can predict what kind of biofuel will properly succeed fossil fuels at the international market reality. In spite of the achievements in biofuels research and processing, a large proportion of biomass is still used for heating purposes in developing countries, causing devastation and increasing CO2 concentration in the atmosphere. Good examples of regional emphasis and hopes are the ethanol production from sugar cane in Brazil and from corn in the USA, as well as, biogas from wastes in Asia. Recently, the German automobile industry pointed out their challenging project to replace the actual inefficient intern combustion motors by batteries or hydrogen fuel cell driven vehicles, towards world green mobility free of CO2 – emissions for small cars. So, biohydrogen produced from renewable feedstocks will assume a strategic position in the next decades. Differently from oil, which has hydrocarbons as its main component, biomass has a large diversity of compounds, like, carbohydrates, fat acids or even lignocellulosic complex materials, available all over the world. However, such chemical biodiversity of compounds and structure bring technical barriers relating to high yields of biomass conversion into biofuels. In this sense, promising sustainable processes for cellulose materials and microalgae are being thermochemically developed to convert these materials into SYNGAS, a convenient intermediate to fuel and chemicals. Due to their high productivity, versatile and simple chemical composition, microalgae can be produced in semi arid regions, unproductive land and any source of water. Moreover, microalgae cultivation could absorb CO2 from thermoelectric power plants increasing synthetic photosynthesis yield and reducing CO2 concentration in the atmosphere. This seems to be a strategic model to convert bioresources into biofuels to attend future automobile requirements, as well as, chemical industry.