Palmester oil is a clean burning alternative fuel produced from palm oil. Palmester oil contains no petroleum, but it can be blended at any level with petroleum or diesel to create a biodiesel blend (palm oil with diesel). It can be fed into Compression Ignition (CI) engines with little or no modifications. Palmester oil is simple to use, biodegradable, nontoxic, and essentially free of sulfur and aromatics. In the present investigation, palmester was prepared by transesterification method to make it suitable for use in CI engine, and the performance of the engine was evaluated using the developed biodiesel blends. Six specific blends were prepared for testing, i.e., B10 (10% palmester + 90% diesel), B20 (20% palmester + 80% diesel), B30 (30% palmester + 70% diesel), B40 (40% palmester + 60% diesel), B50 (50% palmester + 50% diesel) and B100 (100% palmester). The performance of the engine using palmester oil blends was evaluated in a 4-stroke single cylinder CI engine and compared with the performance with diesel. Results indicated that B20 has closer performance to diesel and B100 has lower Brake Thermal (B Th) efficiency mainly due to its higher viscosity compared to diesel. However, B20 palmester blend oil showed reasonable efficiencies of lowest Specific Fuel Consumption (SFC), brake thermal efficiency, Brake Horse Power (BHP), mechanical efficiency, volumetric efficiency and exhaust gas temperature as compared to diesel.

The esters of vegetable oils and animal fats are known collectively as biodiesel, a renewable alternative fuel that has been shown to be a direct replacement for diesel in compression ignition engines. According to Van Gerpen et al. (2007), biodiesel has an energy content that is about 12% less than petroleum-based diesel on a mass basis. It has a higher molecular weight, viscosity, density, and flash point than diesel fuel. When biodiesel is compared with conventional diesel fuel in engine tests, the power and fuel consumption are nearly in direct proportion to the fuel's energy contents. Biodiesel is an oxygenated fuel, with 10% to 11% oxygen by weight, and produces less unburned hydrocarbons (HC), carbon monoxide (CO), and Particulate Matter (PM) than conventional petroleum diesel. Carbon dioxide (CO₂) is recycled through the process of photosynthesis in growing the oilseeds, thus making biodiesel nearly CO₂ neutral. Oxides of nitrogen (NO_x) increase by 10% to 15%, when 100% biodiesel is used as fuel. Biodiesel fuels are good for the environment because they are also readily biodegradable, a benefit in case of spills.

Continued use of petroleum-sourced fuels is now widely recognized as unsustainable because of depleting supplies and the contribution of these fuels to the accumulation of CO₂ in the environment. Renewable, carbon-neutral transport fuels are necessary for environmental and economic sustainability. Biodiesel derived from oil crops is a potential, renewable and carbon-neutral alternative to petroleum fuels.

For countries which produce oil crops, vegetable oil is a potential source of alternative fuel. Over the years, there have been many attempts to use various types of vegetable oil directly in diesel engines. These include palm oil, soybean oil, sunflower oil, safflower oil, coconut oil, rapeseed oil, jatropha oil, etc. Palm oil is one of the promising renewable biofuels.

Mechanical Engineering Journal, Performance Evaluation, Palmester Oil Blends, Compression Ignition Engines, Conventional Petroleum Diesel, Petroleum Fuels, Vegetable Oils, Global Warming, Transesterification, Environmental Protection Agency, Experimental Investigations, Brake Specific Fuel Consumption.