CHAPTER ONE
INTRODUCTION
Extraction other-wise called leaching is the preferential solution of one or more constituents of a solid mixture by contact with a liquid solvent. This unit operation, is one of the oldest in the chemical industries, the have been given many names, depending to some extent upon the technique used for carrying it out extraction of oil from Soybeans seeds can be carried out using any of the two solid-liquid extraction methods namely: mechanical extraction method or the used of solvent other- wise called mass-transfer method. The yield of the second method is higher but contains more impurities than the first method and it requires another unit operation (distillation) in purifying it better. The success of an extraction and the technique to be used will vary frequently depending upon any prior treatment which may be given to the solid. In some instance small particles of the soluble material are completely surrounded by a matrix of insoluble matter. The solvent must then diffuse into the mass, and the resulting solution must diffuse out before a separation can result. Crushing and grinding of such solids will greatly alliterate the leaching action, since then the soluble portions are made more accessible to the solvent. Seeds like Soybeans seeds and other vegetable seeds are cellular in structure, and the natural products to be leached from this material are usually found inside the cells, if the cell walls remain intact upon exposure to a suitable solvent, the leaching involves osmotic passage of the solute through the cell walls. This may be slow, but is impractical and sometime undesirable to grind the material small enough to release the contents of individual cells. One constitutes a well-defined class of neutral organic substance, which are essential constituents of all forms of plant and animal life. They are soluble in other and organic solvents but not in water. Commercial oils are however from a relatively few member of the plant and animal kingdom available forms. They are primary a product of agriculture although these is also a considerably production from uncultivated - tropical plants and from mature animals. Oil can be grouped into edible and non-edible depending on the amount of unspecified matters and impurities. Owing to the fact that the use of oil from crop seed as a major raw materials has increased, in recent years their has been the need for extended and numerous research works based on the extraction of these oil. From its seeds as economically efficiently as possible. The only possible way of obtaining large quality of oil from oil being vegetable or plant materials is by extraction and this could best be achieve using leaching process. This process can be accomplished by a variety of ways but as might be expected its efficiency depends to an extent and obtaining intimate contact between the liquid solvent and the solid containing the solute. Leaching reduces the oil content in the residue to about 0.5-1.5 percent as compared. With about 5-9 percent by mechanical process. The types of solvent available for leeching include 17-hexane, petroleum, ether, benzene ethyl ether etc which are high petroleum fractions. The choice of a solvent for extraction is a function of its volatility and relative volatility for easy separation by distillation.  Soybeans oil is used primary in homes for cooking and also as an industrial raw material for other usefully products. 1.2    AIMS/ OBJECTIVES OF THE PROJECT To extract oil from Soybeans seeds and compare the yields obtained using different solvents and standard. Also the project is aimed at characterizing the extracted oil by determining the physical and chemical properties of the oil.