Petroleum is Nigeria’s most valuable natural resource, making the country one of the world’s leading producers of crude oil. One of its key refined products is Premium Motor Spirit (PMS), commonly known as petrol. PMS is primarily used as fuel for combustion engines and is mainly composed of aliphatic hydrocarbons derived from the fractional distillation of petroleum. Given its significance in Nigeria’s daily activities, it is essential to understand the product and identify its key components.
One noticeable physical characteristic of PMS is its seemingly colourless appearance. However, you may have observed that some fuels appear in different colors. While PMS is naturally colorless, it is often dyed in various colors to indicate specific compositions or usage restrictions.
Another crucial component of PMS is its quality. High-quality PMS can remain stable for over six months when stored properly, although it will degrade over time due to its volatile nature. To prevent oxidation or contamination with water vapor, PMS must be stored in an airtight container.
To protect sensitive engines, PMS contains antiknock additives. When used in high-compression internal combustion engines, PMS may auto-ignite, leading to engine knocking. This is why some variants, such as leaded petrol or lead replacement petrol (LRP), are produced for engines that require leaded fuel. Unleaded petrol is now more common due to environmental concerns.
Additionally, PMS includes fuel stabilisers, antioxidants, and metal deactivators to enhance engine performance and longevity.
A notable advancement in PMS formulation is the inclusion of oxygen-bearing compounds. Oxygenate blending introduces compounds like MTBE, ETBE, TAME, TAEE, ethanol, and biobutanol. These compounds reduce carbon monoxide emissions and unburned fuel in vehicle exhaust. Ethanol and detergents in PMS are also critical, as they help reduce internal engine carbon buildup, improve combustion, and facilitate cold starts, especially in colder climates.
In summary, the components of PMS—ranging from hydrocarbons and antiknock agents to oxygenates and detergents—contribute to its efficiency and environmental impact, making it an essential product in modern-day fuel usage.
