GCSE Chemistry - Crude Oil and Fractional Distillation #53

Summary

This video explores the fractional distillation process of crude oil, a fossil fuel derived from ancient organic matter. It explains how different hydrocarbons within crude oil are separated based on their boiling points, yielding products like bitumen for road surfacing, heavy fuel oil, and lighter fuels such as diesel, petrol, and kerosene. The video also touches on the potential for 'cracking' longer-chain hydrocarbons and the use of petrochemicals as raw materials for various industries, highlighting the importance of this process in our daily lives.

Takeaways

• 🌿 Crude oil is a fossil fuel derived from the remains of dead plants and animals, particularly plankton, that have been subjected to high pressures and temperatures underground for millions of years.
• 🚧 Crude oil is a complex mixture of hydrocarbons, predominantly alkanes, which are compounds consisting of hydrogen and carbon.
• 💧 The formation of crude oil is a lengthy process, making it a finite and non-renewable resource.
• 🔩 Fractional distillation is the primary method used to separate the various hydrocarbons in crude oil due to their differing boiling points.
• 🔥 The distillation process involves heating the crude oil to a gaseous state and then passing it through a fractionating column where it is separated based on boiling points.
• ⛽ The longest-chain hydrocarbons, with the highest boiling points, condense first and are used for products like bitumen for road surfaces and heavy fuel oil.
• 🚗 Shorter-chain hydrocarbons with lower boiling points are used as fuels for vehicles, such as diesel, petrol, and kerosene for jet engines.
• 🔥 Hydrocarbons with very low boiling points, like LPG (propane and butane), remain gaseous throughout the distillation process and are used for cooking and heating.
• 🔨 Longer-chain hydrocarbons that are poor as fuels can be further processed through cracking to produce smaller, more useful hydrocarbons.
• 🏭 Petrochemicals, derived from crude oil, serve as raw materials for various industries, including the production of solvents, lubricants, polymers, and detergents.

Q & A

What is crude oil and where does it come from?

Crude oil is a fossil fuel derived from the remains of dead plants and animals, particularly plankton, that died millions of years ago and were buried in mud. It is formed naturally under high pressure and temperature conditions over millions of years.

Why is crude oil considered a non-renewable resource?

Crude oil is considered non-renewable because it takes millions of years to form from organic biomass, and if extracted and used at the current rate, it will eventually run out.

How does the fractional distillation process separate the components of crude oil?

Fractional distillation separates the components of crude oil by heating it and taking advantage of the different boiling points of the compounds. It involves heating the crude oil into a gas, then passing it through a fractionating column where it cools and condenses at different levels based on its boiling point.

What are the first compounds to condense and drain out of the fractionating column during distillation?

The first compounds to condense and drain out are the hydrocarbons with the longest chains, which have the highest boiling points. These include substances like bitumen used for road surfacing and heavy fuel oil.

What are the uses of the longer-chain hydrocarbons that condense early in the distillation process?

Longer-chain hydrocarbons that condense early are used for making bitumen for road surfaces, heavy fuel oil for heating, and can be further processed into lubricating oils.

Which hydrocarbons have lower boiling points and thus stay in the gaseous state longer during distillation?

Shorter chain hydrocarbons have lower boiling points and remain in the gaseous state longer as they rise up the fractionating column. These include fuels like diesel, petrol, and kerosene.

What products can be obtained from the shorter chain hydrocarbons in crude oil?

Shorter chain hydrocarbons yield products like diesel for vehicles, petrol for cars, and kerosene for jet engines after distillation.

What happens to the hydrocarbons that remain as gas throughout the distillation process?

Hydrocarbons with very short chains and low boiling points, such as propane and butane in liquefied petroleum gas (LPG), remain as gas throughout the distillation process.

How are the hydrocarbons at the top of the fractionating column different from those at the bottom?

Hydrocarbons at the top of the column are shorter chains and more flammable, making them ideal for fuels, while those at the bottom are longer chains, often poor as fuels, and are used for other purposes or processed further.

What is the term for the substances derived from crude oil used as raw materials in the petrochemical industry?

The substances derived from crude oil used as raw materials in the petrochemical industry are called petrochemicals.

What other uses do petrochemicals have besides being fuels?

Besides being used as fuels, petrochemicals serve as feedstock for making solvents, lubricants, polymers, and detergents in the petrochemical industry.

Outlines

00:00

🌿 Crude Oil and Fractional Distillation

The video discusses crude oil, a fossil fuel extracted from underground, primarily composed of hydrocarbons including alkanes. It explains the natural formation of crude oil from the remains of dead plankton under high pressure and temperature over millions of years. The video emphasizes that crude oil is a non-renewable resource due to its lengthy formation process. To utilize it effectively, the process of fractional distillation is employed to separate its various hydrocarbon components based on their boiling points. This involves heating the oil to gaseous form, then passing it through a fractionating column where different compounds condense into liquids at varying temperatures. Longer-chain hydrocarbons, like bitumen and heavy fuel oil, condense at lower temperatures, while shorter-chain ones, such as those used for diesel, petrol, and kerosene, remain gaseous longer and condense higher up the column. The video concludes by mentioning that some hydrocarbons, like LPG (propane and butane), have such low boiling points they remain gas throughout the process.

05:01

🔬 Petrochemicals and Their Applications

The second paragraph delves into the broader applications of petrochemicals, which are the substances derived from crude oil. These petrochemicals serve as raw materials for a wide range of products in the petrochemical industry, including solvents, lubricants, polymers, and detergents. The paragraph wraps up the video by inviting viewers to like and subscribe for more informative content, hinting at a follow-up video that will explore the process of cracking, which breaks down long-chain hydrocarbons into smaller, more useful molecules.

Keywords

💡Crude Oil

Crude oil is a fossil fuel extracted from the earth, primarily composed of hydrocarbons. It is formed from the remains of dead plants and animals, particularly plankton, that have undergone transformation under high pressure and temperature over millions of years. In the video, crude oil is highlighted as a finite resource that is used for various purposes, emphasizing its importance and the need for its efficient separation into different components.

💡Fractional Distillation

Fractional distillation is a process used to separate the different components of crude oil based on their boiling points. It involves heating the oil to turn it into a gas and then passing the gas through a fractionating column where it cools and condenses at different levels, allowing for the separation of various hydrocarbons. The video explains how this process is crucial for obtaining different types of fuels and other products from crude oil.

💡Hydrocarbons

Hydrocarbons are organic compounds consisting only of hydrogen and carbon atoms. They are the main constituents of crude oil and include various types such as alkanes, which are the focus of the video. Hydrocarbons are used in a wide range of applications, from fuels to lubricants, and their separation through fractional distillation is a key theme in the video.

💡Alkanes

Alkanes are a type of hydrocarbon with single bonds between carbon atoms, making them saturated hydrocarbons. They are the most common compounds in crude oil and are discussed in the video as the primary constituents that are separated during fractional distillation. Alkanes with different chain lengths are used to produce various products like gasoline, diesel, and lubricating oils.

💡Bitumen

Bitumen, also known as asphalt, is a heavy, viscous hydrocarbon that remains液态 at the end of the fractional distillation process due to its high boiling point. It is used for road construction and other applications. The video mentions bitumen as an example of a product obtained from the heavier fractions of crude oil.

💡Fuel Oil

Fuel oil is a fraction of crude oil that can be used for heating or as a fuel in certain types of engines. It is typically a heavier hydrocarbon and is mentioned in the video as one of the products that can be further separated from the heavier fractions of crude oil for specific uses.

💡Diesel

Diesel is a middle distillate fraction of crude oil that is used as fuel for diesel engines. It is produced through fractional distillation and has a boiling point that allows it to be used effectively in compression ignition engines. The video explains how diesel is one of the products obtained from the shorter chain hydrocarbons in crude oil.

💡Petrol (Gasoline)

Petrol, or gasoline, is a lighter fraction of crude oil used as fuel for internal combustion engines in vehicles. It is produced by distilling crude oil at specific temperatures to capture hydrocarbons with the appropriate boiling points. The video highlights petrol as a product derived from the fractional distillation of crude oil.

💡Kerosene

Kerosene is a hydrocarbon fraction with a boiling point that makes it suitable for use as a fuel in jet engines and as a heating oil. It is produced through the fractional distillation process and is mentioned in the video as an example of a product that can be obtained from the distillation of crude oil.

💡Liquefied Petroleum Gas (LPG)

LPG is a gaseous hydrocarbon mixture, primarily composed of propane and butane, which are short-chain alkanes. It remains in gaseous form during the fractional distillation process due to its low boiling point. LPG is used as a fuel in various applications and is highlighted in the video as an example of a lighter fraction obtained from crude oil.

💡Cracking

Cracking is a process in which longer-chain hydrocarbons are broken down into shorter, more useful hydrocarbons. This is particularly useful for heavier fractions of crude oil that are not suitable as fuels. The video mentions cracking as a process that will be explored in more detail in a subsequent video, indicating its importance in the refining of crude oil.

💡Petrochemicals

Petrochemicals are chemical products derived from crude oil, including a wide range of substances from solvents to polymers. They serve as raw materials for various industries and are mentioned in the video as an example of the diverse uses of the components derived from crude oil beyond just fuel production.

Highlights

Crude oil is a fossil fuel consisting of a mixture of hydrocarbons derived from the remains of dead plants and animals.

Crude oil is formed naturally from organic biomass under high pressure and temperatures over millions of years.

The process of extracting crude oil involves drilling into rock formations and pumping the oil to the surface.

Crude oil is considered a finite and non-renewable resource due to its long formation period.

Fractional distillation is used to separate the different hydrocarbons in crude oil based on their boiling points.

The distillation process begins with heating crude oil to turn it into a gaseous state.

A fractionating column is used to separate hydrocarbons, with different sections having varying temperatures.

Long-chain hydrocarbons with high boiling points condense into liquids at lower temperatures in the column.

Bitumen and heavy fuel oil are examples of products obtained from long-chain hydrocarbons.

Shorter chain hydrocarbons with lower boiling points remain gaseous longer and are used for fuels like diesel and petrol.

Kerosene, used in jet engines, is also obtained from the distillation process.

LPG, containing propane and butane, consists of very short-chain alkanes that remain gaseous throughout the distillation.

Long-chain hydrocarbons at the bottom of the fractionation are often used for purposes other than fuel or are processed further.

Cracking is a process that breaks down long-chain hydrocarbons into smaller ones, which will be discussed in a future video.

Petrochemicals, derived from crude oil, serve as raw materials for various industries, including solvents, lubricants, polymers, and detergents.

The video concludes with a call to action for viewers to like and subscribe for more educational content.

Transcripts

in today's video we're going to take a

look at crude oil and see how we can

separate it into its different

components using fractional

distillation crude oil is a fossil fuel

that we get from deep under the ground

and is basically a mixture of lots of

different compounds

nearly all of these compounds though are

hydrocarbons

which contain only hydrogen and carbon

and the most common type of hydrocarbons

are alkanes which we covered in the last

couple of videos

now crude oil is formed naturally from

the remains of dead plants and animals

particularly plankton

that died millions of years ago and were

buried in the mud

then in the millions of years between

then and now the high pressures and

temperatures under the ground turned

this organic biomass into crude oil

as it formed this crude oil soaked into

the rocks and was stored for millions of

years

but we can get it back out by drilling

into the rock and sucking it up to the

surface

as crude oil takes so long to form it's

effectively a finite resource

and if we continue to extract and use it

at the rate that we are now

then one day we'll run out of it

completely

this is why we refer to fossil fuels

like coal oil and gas as non-renewable

fuels

once we've extracted the crude oil from

the ground we need some way to separate

out all of the different hydrocarbons in

the mixture

because they each have different

properties and so we'll use them for

different things

to do this separating we use a process

called fractional distillation

which involves heating the crude oil up

and separating out different compounds

by making use of the fact that the

different compounds all have different

boiling points

the first step is to feed the oil into a

chamber and heat it until most of it has

turned into a gas

we then pass this gaseous mixture into a

fractionating column

which is really hot at the bottom but

gets cooler towards the top

the idea is that these hot gases will

then start to rise up the column

but importantly as soon as they reach a

region that has a lower temperature than

their boiling point

they'll condense into a liquid

the hydrocarbons with the longest chains

so the most carbons have the highest

boiling points

and so they'll quickly condense back

into a liquid and drain out of the

column early on

because it's not hot enough to keep them

in their gaseous states

these are things like bitumen which we

use to surface our roads

and heavy fuel oil

which can be separated further and used

for things like heating oil fuel oil or

lubricating oil

the shorter chain hydrocarbons though

have much lower boiling points

so they'll stay they gas so much longer

as they rise up the column until they

finally reach a cool enough temperature

that they condense into a liquid

this gives us fuels like diesel and

petrol which we're using cars and other

road vehicles

and kerosene which is used in jet

engines

some hydrocarbons though are so short

and have such low boiling points that

they stay as a gas the entire time

for example lpg which stands for

liquefied petroleum gas contains mainly

propane and butane which are both very

short chain alkanes

if we compare these different groups or

fractions the ones towards the top which

are the shorter chains are the most

flammable

and so they tend to make the best

fuels meanwhile the longer chain

hydrocarbons here at the bottom are

often poor fuels

so are instead either used for something

else

or can be broken down into smaller

hydrocarbons in a process called

cracking which we'll take a look at in

the next video

the last thing to point out is that as

well as all of these fairly direct uses

that we mentioned here

petrochemicals which is what we call all

of these substances that we get from

crude oil

can also be used as feedstock

which just means raw materials for the

petrochemical industry

you use them to make things like

solvents lubricants polymers and

detergents

anyway that's all for this video so hope

you found useful

if you did then please do give us a like

and subscribe

and we'll see you next time