ABSTRACT

This project “Extraction of oil from a local seed (groundnut oil) and Characterization” was carried out using ten cups of groundnut seeds that was purchased from a local market in Enugu metropolis.  The oil these seeds were in Enugu using solvent extraction method.  Two different solvents were used in the extraction namely: Ethane and order to compare their yield, physical and chemical properties.

The extraction was carried out using 32og of size-reduced groundnut with 100ml of 17-hexane while 1.5litres a 15ooml of ethanol was used on 480g of size reduced groundnut seeds.  Ta the end of the extraction operation, the amount of oil-extracted using17-hexane was observed to be far more greater than the amount of oil extracted using ethanol.

The chemical and physical properties of the oil were determined by analysis of the oil.  The physical appearance of 17- hexane extract is light yellow in colour this; true colour of groundnut oil while that the ethanol extract has a light bown colour.  The colour of ethanol on pigments in the size-reduced groundnut seed.

From  the result obtained, it was deduced that 17-hexane remains the best solvent for oil extraction while ethanol is not a good solvent for oil extraction.

The physical and chemical constants/ properties determined were:

PHYSICAL PROPERTIES:

a)                  Solidification point.

b)                  Melting point

c)                  Specific gravity

d)                 Moisture content.

CHEMICAL PROPERTIES

a)                  Acid value

b)                  Saponification value

c)                  Peroxide value

d)                 Iodine value

Form  the analysis camied out on the extracted oil, the results obtained shows that the extracted oil is a pure groundnut oil because  the iodine value which shows the purity of an oil is close to literature value.  The iodine value of he oil extracted is 79.95 while the literature value (standard value) rangers from 94-102.

TABLE OF CONTENT

CHAPTER ONE.

1.1              INTRODUCTION

1.2              SCOPE / OBJECTIVES OF THE PROJECT.

CHAPTER TWO

2.0              LITERATURE REVIEW

2.1       GROUNDNUT SEED

2.2              ADAPTATION

2.3              DISEASES OF GROUNDNUT

2.4              EXTRACTION

2.5              METHODS OF OIL EXTRACTION

2.6              RENDERING

2.7              MECHANICAL EXTRESSION

2.8              SOLVENT EXTRACTION

2.9              GROUNDNUT OIL EXTRACTION

2.9.1        FACTORS AFFECTING RATE OF LEACHING

2.9.2        FACTORS GOVERNING CHOICE OF SOLVENT

2.9.3        LEACHING OF VEGETABLE SEEDS

2.9.4        THEORIES OF SOLVET EXTRACTIONS

2.9.5        UNDISSOLVED OIL THEORY

2.9.6        PHYSICAL PROPERTIES OF VEGETABLE OIL

2.9.7        CHARACTERIZATION OF OILS

2.9.8        SAPONIFICATION VALUE

2.9.9        IODINE VALUE

CHAPTER THREE

3.0       EXPERIMENTAL METHODS

3.1              PREPARATION OF THE SEEDS

3.2              PARTICLE SIZE REDUCTION

3.3              EXTRACTION AND DISTILLATION

3.4              USES OF SOXLILET EXTRACTOR

3.5              DISTILLATION

3.6              SOLIDIFICATION POINT

3.7              MELTING POINT

3.8              SPECIFIC GRAVITY

3.9              DETERMINATION OF MOISTURE CONTENT

3.10          DETERMINATION OF CHEMICAL PROPETIES

3.11          DETERMINATION OF ACID VALUE

3.12          SAPONIFICATION VALUE

3.13          PEOXIDE VALUE

3.14          IODINE VALUE

CHAPTER FOUR

4.0        EXPERIMENTAL RESULTS

CHAPTER FIVE

5.0  DISCUSSION

CHAPTER SIX

6.1              CONCLUSION / RECOMMENDATION

6.2              REFERENCES

6.3              APPENDICES.

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, one of the oldest in the chemical industries, here been given many names, depending to some extent upon the technique used for carrying it out extraction of oil form groundnut 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 purity 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 he 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 groundnut seeds and other vegetable seeds are cellular in structure, and the natural products to be leached form these 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 in is impractical and sometime undesirable to grind the material small enough to release the contents of individual cells.

Oil 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 yeses their has been the need for extended and numerous research works based on the extraction of these oil.  Form 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 leading process. This process can be accomplished by a variety of ways but as might be expected its efficiency depends to an extant an obtaining intimate contact between the liquid solvent and the solid containing he 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 leaching 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.

Groundnut oil is used primary in homes for cooking and also as an industrial raw material for other usefully products.

SCOPE AIMS/ OBJECTIVES FO THE PROJECT

The scope of this research project is to extract oil from groundnut seeds and compare  the yields obtained using different solvents and to standard.

Also the project is aimed at characterizing the extracted oil by determining the physical and chemical properties of the oil.

This material content is developed to serve as a GUIDE for students to conduct academic research