Comprehensive Evaluation Of Feedstock Species Of Woody Plants For Biodiesel And Exploration Of FAME From Sapium Sebferum Roxb. Oils

The issues of crude oil reserves exhausting in near future and the environmental pollution of releasing gases from petroleum-fuelled engines are focused by all countries in world recently. Biodiesel is applicable to storage and transportation, and it is a realistic, renewable and clean fuels with excellent properties as a fossil fuel substitute. The industrialization of biodiesel derived from plant and animal oils, namely FAME (fatty acid methyl ester) which related to our country security and sustainable development. The exploration of woody oil plants in advantage of resources adapts to the state of our country. In present time, the choice and developing feedstock species of woody plants adapting to local area for biodiesel become crucial determination.In order to promote the development of biodiesel industrialization, this thesis put forward a systematic research according to the result of comprehensive evaluation by utilizing Sapium sebferum seed oils (including kernel oil in kernel of seeds and crust oil in outer coat of seeds ) to produce biodiesel in fujian province .Main results of this study demonstrate as following:1 A set of comprehensive evaluation system was put forward to feetstock species of woody plants for biodiesel, and defined 3 hierarchy evaluation indexes relating to the whole industrialization of biodiesel, and through experts survey, build evaluation indexes weight system2 Mostly based on the documents combining field work, a primary investigation of classification and distribution were conducted. Standards of qualitative and quantitative evaluation was determining by analyzing each index. With methods of experimental determination to the quantitative indexes and specialized questionnaire referring to the resource investigation and literature researches, 8 species such as Jatropha curcas, Sapium sebferum, Podocarpus nagi, S. discolor, etc. were choosed by simple evaluation from 41 species of considerable oils tree and shrub in Fujian. Finally, 8 species and storting were comprehensively evaluated by means of FCE(fuzzy comprehensive evaluation). 3 The content of crust oil in Sapium sebferum seed (24.71%) exceed the content of Chinese tallow kernel oil(17.42%), Using Chinese tallow seed oils as the raw material producing biodiesel were more economic benefit. Analysis of the fatty acid composition and physical and chemical characteristics of Chinese tallow seed oils showed: Sapium sebferum seed oil and Chinese tallow kernel oil are mostly unsaturated fatty acids, which are mainly linoleic acid, oleic acid(18:2) and linolenic. Viscidity and acid value of the crude Chinese tallow seed oil and kernel oil were high, so it needs to reduce the content of gum which are mainly contain phosphatide and deacidfy before making biodiesel.4 Preesterification could reduced the acid or FFA(free fatty acid) contents of raw material oils to less than 0.5%, meanwhile reduced the phosphatide less than 12.0μg/ml at optimum condition: 0.5w/w methanol-to-oil ratio in the presence of 1.2% w/w H₂SO₄ as an acid catalyst in 1h reaction 60℃.5 Important variable affecting the esterfying rate of kernel oil in the transesterification process was: the methanol to oil molar ratio >the concentration of catalyst KOH > reaction temperature >reaction time; Through the orthogonal experiment L₉(3⁴), the optimum combination for transeserification reaction was found to be 7:1 methanol to oil molar ratio, 1.4%w/w KOH to oil as alkaline catalyst to produce biodiesel at 55℃. The final yield for FAME was achieved about 95% in 1h, so as the Chinese tallow seed oil due to its similar characteristic of reaction.6 Characteristic peaks indicating frequency in infarared spectrograms of the FAME from kernel oil and Chinese tallow seed oil were 1013.03 cm^-1 and 1014.94 cm^-1 indicated the absorption of functional group c-o-c in FAME; The maximum absorbing frequency in the same spectrograms indicated the expansion vibration by the functional group c=o in FAME were 1736.21 cm^-1 and 1740.30 cm^-1. The peaks of the main functional groups in the long fatty acid trains could also be found .7 The properties of FAME from kernel oil and Sapium sebferum seed oil as fuel were also analyzed .The results showed that indexes met to the standard of light diese in our country except the cetane number of FAME from kernel oil and Chinese tallow seed oil made in this study were lower than fossil diesel standard at 1-2 point. Flash point, cold filter point and acid value of the products have advantage to the fossil diesel, There are some gaps compared with the American and Germany biodiesel standard , and the thesis put forward some proposal that rectifying process could improve the quality of the products. Blending fossil fuel could overcome the deficiency of lower cetane, and could use on the petroleum-fuelled engines as a substitute.8 FAME from kernel oil and seed oil in Sapium sebferum full mutual soluble with the diesel at any ratio; The Be(brake specificc fuel consumption) of the products mix-buening are slightly higher than fossil diesel, and similar at lower blending ratio,The blend at lower ratio could full substitute the fossil diesel at lower ratio.