Gasoline vs. Kerosene: Key Differences and Uses

Understanding the nuances of petroleum products is essential for both industrial professionals and everyday consumers. While both originate from crude oil, Gasoline and Kerosene serve very different purposes due to their chemical compositions.

1. Are Gasoline and Kerosene the Same?

No, they are not the same. Although both are derived from the distillation of crude oil, they are separated at different temperatures. To understand the basics, you might first want to read What is gasoline and What is kerosene.

The Key Differences:

Volatility: Gasoline is highly volatile and evaporates quickly at room temperature, whereas kerosene is less volatile and more stable.
Molecular Structure: Kerosene has a higher molecular weight and longer carbon chains ( $C_{12}$ to $C_{15}$ ) compared to gasoline ( $C_{4}$ to $C_{12}$ ).
Flash Point: Gasoline has a much lower flash point (approx. $-43°C$ ), making it highly flammable, while kerosene has a higher flash point (above $38°C$ ), making it safer for storage and heating.

2. Why Can’t You Use Kerosene in Your Car?

One of the most common questions is why kerosene isn’t a substitute for car fuel. The primary reason is the Octane number. Modern car engines are designed for high-octane, fast-burning fuels.

Kerosene has a much lower octane rating. If used in a gasoline engine, it would cause “knocking” or pre-ignition, which can lead to catastrophic engine failure. Additionally, the Gasoline production process involves additives that clean engines, which kerosene lacks. If you are interested in fuel variations, you can explore the Difference between diesel and gasoline or the properties of Unleaded gasoline and E85 gasoline.

3. Comparison Table: Gasoline vs. Kerosene

Feature	Gasoline (Petrol)	Kerosene (Paraffin)
Boiling Point	$30°C$ to $200°C$	$150°C$ to $300°C$
Primary Use	Internal combustion engines	Heating, jet fuel, lighting
Volatility	Very High	Low
Pollutants	High CO2 and NOx	Lower particulates, but produces soot
Burn Rate	Extremely Fast	Slow and Steady

4. Usage and Pollutants: Which is Cleaner?

Kerosene is widely used as a heating fuel and as a base for aviation. In fact, you can see a Comparison of kerosene and jet fuel to understand its specialized applications.

Combustion Speed: Gasoline burns much faster, providing the “explosion” needed for high-speed pistons.
Pollutants: Kerosene generally burns “cleaner” in terms of fewer volatile organic compounds (VOCs) when used in lamps or heaters, but it produces more soot if not properly oxygenated. Gasoline, especially when leaded, historically produced more toxins, though modern Unleaded gasoline has mitigated this.

5. Can They Be Mixed?

Mixing gasoline and kerosene is not recommended.

In a car: Adding kerosene will lower the octane rating and damage the fuel injectors.
In a heater: Adding gasoline to a kerosene heater is extremely dangerous and can cause an explosion due to gasoline’s high volatility.

For more technical comparisons, see Comparison of naphtha and gasoline or Comparison of naphtha and kerosene.

6. Other Petroleum Products

The refinery process yields many other vital materials such as LPG, Bitumen, Sulfur, and Base oil. These are all part of the broader category of Petroleum products.