Vegetable oil as Alternate Fuel:
oils used as DF as well as neat methyl esters prepared from vegetable oils or
animal fats and blends of conventional diesel fuel with vegetable oils or
methyl esters. Most vegetable oils are triglycerides (TGs; triglyceride = TG).
Chemically, TGs are the triacylglycerol esters of various fatty acids with glycerol.
The published engineering literature strongly indicates that the use of SVO
will lead to reduced engine life. This reduced engine life is caused by the
buildup of carbon deposits inside the engine, as well as negative impacts of
SVO on the engine lubricant. Both carbon deposits and excessive build-up of SVO
in the lubricant are caused by the very high boiling point and viscosity of SVO
relative to the required boiling range for diesel fuel. The carbon buildup
doesn’t necessarily happen quickly but instead over a longer period. These
conclusions are consistent across a significant body of technical information
in multiple articles and reports. Biodiesel is an alternative fuel that can be
made from SVO in a chemical process called transesterification that involves a
reaction with methanol using caustic soda (sodium hydroxide) as a catalyst.
Biodiesel has substantially different properties than SVO and results in better
engine performance. In particular, biodiesel has a lower boiling point and
viscosity than SVO. Because of its improved qualities, vehicle and engine
manufacturers generally approve the use of biodiesel blends in their products,
though not all approve blend levels as high as 20%.