CHAPTER ONE
INTRODUCTION
Biodiesel is an alternative fuel made from renewable biological sources such as vegetable oil and animal fats (Raja et al., 2011). Due to the depleting world’s petroleum reserves, threatening to run out in the foreseeable future and the increasing environmental concerns, there is a great demand for alternative sources of petroleum-based fuel including diesel and gasoline (Sambo, 1981; Munack et al., 2001). Indiscriminate extraction and increased consumption of fossil fuels have led to the reduction of the underground-based carbon resources (Ramadhas et al., 2004). Biofuels are produced from renewable sources; they do not add to the stock of total carbon-dioxide in the atmosphere. These plant forms remove carbon-dioxide from the atmosphere and give up the same amount when burnt within a few years. Hence, biofuels are considered to be “CO2 neutral” (Ramadhas et al., 2004). The primary goals of National Energy Policy are to increase the energy supplies using mixtures of domestic resources and to reduce our dependency on imported oil or petroleum. As a domestic renewable energy source, biomass offers an alternative to conventional energy sources and supplements national energy security, economic growth and environmental benefits (Ma and Marcus, 1999). Currently, biodiesel is considered a promising alternative due to its renewability, better gas emission, non toxicity and its biodegradability (Hossain et al., 2010). Plant oil and animal fats contain three ester linkages between fatty acids and glycerol which makes them more viscous. Among the techniques applied to overcome the difficulties encountered in using vegetable or animal oil in engines, transesterification of oil to biodiesel seems the most promising (Zhang et al., 2003). The high viscosities of vegetable oils are reduced through the process of transesterification (Alamu et al., 2008). The production of biodiesel from edible and non edible oil has progressively affected food uses, price, production and availability (Rashid et al., 2008). Vegetable oil seeds that do not compete with traditional food crops are needed to meet existing energy demands (Xu and Marcus, 2009). Reducing the cost of the feedstock is necessary for biodiesel’s long-term commercial viability. In order to achieve production cost reduction and make biodiesel more competitive with petroleum diesel, low cost feedstocks, such as non-edible oils, waste vegetable oils could be used as raw material (Xiaohu and Geg, 2009). In this research therefore, attempt is being made to explore the oil of Luffa cylindrica seed from Nigeria in an industrial process for the production of biodiesel.
- Luffa cylindrica plant.
Loofa is derived from the cucumber and marrow family, and originates from America (Mazali and Alves, 2005). Luffa commonly called sponge gourd, loofa, vegetable sponge, bath sponge or dish cloth gourd, is a member of cucurbitaceous family. The number of species in the genus Luffa varies from 5 to 7. Only 2 species L. cylindrica and L. acutangula are domesticated. 2 wild species are L. graveolens and L. echinata. Loofa sponge is a lignocellulosic material composed mainly of cellulose, hemicelluloses and lignin (Rowell et al., 2002). The fibers are composed of 60% cellulose, 30% hemicelluloses and 10% lignin and the fruits smooth and cylindrical in shape.
Luffa cylindrica has alternate and palmate leaves comprising petiole. The leaf is 13 and 30 cm in length and width respectively and has the acute-end lobe. It is hairless and has serrated edges. The flower of L. cylindrica is yellow and blooms during August-September. The plant is cultivated in many countries, including Brazil, where its cultivation has an increasing economic importance (Mazali and Alves, 2005).
Luffa cylindrica is a sub-tropical plant, which requires warm summer temperatures and long frost-free growing season when grown in temperate regions. It is an annual climbing plant which produces fruit containing fibrous vascular system. It is a summer season vegetable. It is difficult to assign with accuracy the indigenous areas of Luffa species. They have a long history of cultivation in the tropical countries of Asia and Africa. Indo-Burma is reported to be the center of diversity for sponge gourd. The main commercial production countries are China, Korea, India, Japan and Central America (Bal et al., 2004).
