CHAPTER ONE    

1. INTRODUCTION

1.1 Backgroundof study

Worldwide petroleum-based energy resources are being depleted – onshore crude oil production peaked decades ago but our demands for petroleum are still going up (McCarthy, et al.2011). The United States’ continued dependency on imported petroleum, particularly from the Middle East, has become an important national security issue (John, et al.1998). Competition for global energy supply from emerging economic powers such as China and India has added to the urgency for searching and developing alternative energy sources that help us reduce our dependency on imported oil. Lastly, environmental concerns such as pollution and global climate changes provide further motivation to address the energy challenge that we face today (Fazal,et al.2011).

Biofuels, which are fuels derived from biomass such as vegetable oil, corn, soybeans, sunflowers, algae, wood chips, etc., are ideally suited for meeting the future energy challenges because they do not add to global climate changes. This is attributed to the fact that plants use CO2 to grow during the photosynthesis process; consequently, the CO2 formed during combustion of biofuels is balanced by that absorbed during the annual growth of plants used as the biomass feedstock (Karavalakisand Bakeas 2010). Another key advantage of biofuels over other alternative energy sources is that they can be burned (either alone or mixed with petroleum-derived gasoline) in existing internal combustion engines (Knothe, 2010). Moreover, we can utilize current infrastructure such as pipelines, delivery trucks, and fueling stations to transport and distribute biofuels.

This report focused on the production of biodiesel (which is an important biofuel) from vegetable oils. With the conventional technology, vegetable oil mixed with alcohol (e.g., ethanol) reacts in large-scale batch reactors and in the presence of an alkaline liquid catalyst (e.g., NaOH or KOH) to form methyl esters or biodiesel and glycerol or glycerine. The transesterification reaction can take up to 12 hours or longer to complete; and at the end of the reaction, it is necessary to use an acid to neutralize the liquid catalyst and to separate biodiesel and glycerol from the product mixture. Apart from the increased costs in their separation and recovery after the transesterification reaction, the alkaline catalysts are corrosive to the equipment and will readily react with free fatty acids to form soaps, an undesired byproduct. It is therefore of interest to explore alternative approaches to the production of biodiesel from vegetable oils, which can raise production efficiency and lower production costs (William, 2010).

1.2              Scope of the study

This study evaluates the effect of combustible flames of biodiesel on growth and haematological properties of rats exposed to it over a period of ten days. This study will as well be used as a reference material for further investigation into the toxic effect of vegetable-oil-biodiesel on all living things, as well as evaluation of other areas of toxicity.

1.3 Aimof the study

The aim of this study is to clarify whether the smoke generated from biodiesel will have any toxic effectan albino-rat.

1.4Objective of the study

The objective of this investigation is to study the effect of vegetable oil biodiesel on the tissues of an albino-rat (Rattus novergicus) such as blood, serum, heart, lung and liver; with emphasis on the following areas of interest such as:

• The extraction of biodiesel as an alternative to the use of conventional diesel in automobile engine operation.
• Analyzing the extracted biodiesel and fuel diesel used in making the blends.
• To determine the toxicological effect of smoke from various blends of biodieselon growth and haematological properties of rats exposed to it over a period of ten days.

1.5Relevance of study

This study serves as a platform for determining the quality of different diesel grades based on their toxicity level and risk to health, so as to secure environmental benefits and promote sustainable development.