Composite biodiesel manufacturing

Fatty acids react with alkaline catalysts to form catalytically inactive soaps (3). The chemical reaction consumes one mole of fatty acid per mole of alkaline catalyst. Although fatty acid composition of the starting material varies, the content determined by titration reflects the amount of catalyst that would be consumed in a chemical reaction. By calculation, it may be determined that one gram of fatty acid (expressed as oleic acid) will react with about 0.2 g of anhydrous potassium hydroxide or 0.14g of anhydrous sodium hydroxide. Often, additional catalyst must be added to esterify a vegetable oil containing higher levels of fatty acids (3). Conversely, acid catalysts are not inactivated by fatty acids (3). In a unique reaction, fatty acids produced during biodiesel manufacture are actually used as a catalyst in their own esterification (see below). 

Official methods of chemical analysis of conventional diesel are often not adequate to characterize biodiesel. Tests for the levels of sulfur and aromatic components in biodiesel are useful but usually reveal that the concentrations of compounds containing these atoms or functional groups are very low. Analysis of biodiesel chemistry can reveal characteristics conferred by the source of the oU, the method of manufacture, and duration of storage (20, 21). For example, free and bound glycerol is measured to ascertain if biodiesel has been completely formed during synthesis. Fatty acid content, residual soaps, iodine value, peroxide value, and fatty acid composition all may reflect the quality of biodiesel (Table 1) but are unimportant and inapplicable in conventional diesel fuel quality determination. 

The pyrolysis products of vegetable oils and wood are highly dependent on the chemical composition of the raw material, and the elemental composition of biofuels typically resembles that of biomass. One possibility is to apply fast pyrolysis to these raw materials directly or after their alkaline hydrolysis for manufacturing liquid fuels (mainly biodiesel).An interesting approach is also the direct pyrolysis of the CTO soap for producing biofuel. In this process concept, sodium could also be recovered simultaneously in the form of Na2C03, thus eliminating, for example, the... 

Starch and sugar crops like wheat and sugar beet, as well as bioethanol, can be used to produce carbohydrates for use in the manufacture of plastics, adhesives and surface coatings. Oilseed crops such as oilseed rape and sunflowers can, as well as biodiesel, produce lubricants, surfactants and slip agents. The main fibre crops such as flax, hemp and cereal straw can be used for making paper, textiles, insulation material and bio-composites for the car industry. 

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