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The crude oil that comes out of the ground is useless on its own. However, once the crude oil is refined, it is used to produce gasoline, diesel fuel, paraffin wax, and even plastics. What is crude oil and how is it turned into so many different things? The answer to the question of crude oil’s multiple uses is fractional distillation and cracking. Fractional distillation and cracking are essential components in turning crude oil into useful products.

What is crude oil?

Crude oil is made from hydrocarbons, which are organic compounds comprised of hydrogen and carbon atoms linked into chains. The length of the hydrocarbon chain determines its boiling point, viscosity, color, and flammability point. These factors are important for the fractional distillation and cracking processes.

What is fractional distillation?

The fractional distillation process takes advantage of the difference in boiling points to sort out the different hydrocarbon lengths. Long hydrocarbon chains require more heat to turn into vapor. The usual form of long chains is the thick, liquid state of crude oil or a waxy solid. Short hydrocarbon chains require little heat to vaporize and are usually in a gaseous form or a volatile liquid.

Fractional distillation involves separating the crude oil into its different parts. The fractional distillation process starts by heating up the material to over 400 degrees Celsius in order to vaporize it. Then, the vapor goes into the bottom of a fractionating column. It is during this part of the fractional distillation process that the crude oil gets separated.

A fractionating column is a hollow, vertical tower. Inside the tower, at specific heights, are distillation plates. As the vapor rises, it begins to cool down and transitions into a liquid state. The fractional distillation plates collect the distillates and siphon them off. The vapor enters the column at over 400 degrees Celsius. As they start to cool down, the longer hydrocarbon chains return to a liquid state. This is the point during the fractional distillation process when asphalt, paraffin wax, and lubricating oil emerge, usually exiting the column at the bottom.

As the vapor rises, cooling to 370 degrees, the fuel oil emerges and collects on the fractional distillation plates. As the vapor continues to rise, it cools to 300 degrees, and diesel oil is produced. At 200 degrees, kerosene is produced and at 150 degrees, gasoline is produced. What is left at this point of the fractional distillation process emerges at the top of the column in gas form.

What is cracking?

The fractional distillation process does an efficient job in breaking down crude oil into useful products. However, the marketplace has more use for liquid gasoline and diesel fuel than it does asphalt or fuel lubricants. Unfortunately, the fractional distillation process produces too much asphalt and fuel oil, and not enough of the lighter liquid distillates like gasoline and diesel fuel. A process known as cracking breaks down the longer crude oil hydrocarbon chains into smaller components. Cracking can be done with high temperatures or with the use of a catalyst.

Thermal cracking of crude oil involves heating the heavier distillates (like asphalt) to temperatures over 800 degrees Celsius, which breaks down the hydrocarbon chains. Catalytic cracking uses a catalyst to cause a chemical reaction to break the hydrocarbon chain. Fluid catalytic cracking uses a hot catalyst fluid to crack crude oil into gasoline and diesel oil.

If you are in need of wholesale fuel products, contact us here at Kendrick Oil. We offer high quality products and services to customers in New Mexico, Texas, Kansas, and Oklahoma. Call us today at 1(800) 299-3991. You can also connect with us via email by clicking on Contact Us.