INTRODUCTION
 
1.1 PREAMBLE
 
The environmental threats posed by the fossil fuels are currently a major global concern. Fossil fuels are increasingly associated with the emissions of greenhouse gases, majorly CO2, leading to climate change, emergence of drought, spread of diseases and variation in population sizes of both plant and animal species (Lashof and
Ahuja, 1990). The depletion of the world’s crude oil reserve, increasing crude oil prices, and issues related to conservation have brought about renewed interest in the use of bio-based materials. Fossil fuels such as petroleum, coal and natural gas, which have been used to meet the energy needs of man, are associated with negative environmental impacts such as global warming (Munack et al., 2001; Saravanan et al.,
2007). Supply of these non-renewable energy sources is threatening to run out in a foreseeable future (Sambo, 1981; Munack et al., 2001). It has been widely reported that not less than ten major oil fields from the 20 largest world oil producers are already experiencing decline in oil reserves.
The contact pressures between devices in close proximity and moving relative to each other are usually sufficient to cause surface wearing, frictions and generation of excessive heat without protector (Hassan et al. 2006). These friction, wear and excessive heat have to be controlled by a process or technique called lubrication. Lubrication is the process or technique employed in reducing wear or tear of one or both surfaces in close proximity and moving relative to each other by interposing a substance called lubricant.