Crude Oil - Fractional Distillation & Combustion Flashcards Preview

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Flashcards in Crude Oil - Fractional Distillation & Combustion Deck (19):
1

What is crude oil?

A mixture of hydrocarbons.

2

What happens during the process of fractional distillation that separates crude oil into fractions?

• Vaporised crude oil is fed into the bottom of a column.
• The column is hot at the bottom and cold at the top.
• The fractions distill off at different levels (lower boiling points condense at the top, higher boiling points condense at the bottom).

3

What is the order of the main fractions obtained from crude oil?

• Refinery gases (LPG)
• Gasoline
• Kerosene
• Diesel
• Fuel oil
• Bitumen

4

What are refinery gases used for?

Heating and cooking - e.g. gas cylinders for barbecues.

4

What is gasoline (petrol) used for?

Is is used as a fuel for cars.

5

What is kerosene (paraffin) used for?

It is mainly used as aviation fuel for jet aircrafts.

6

What is diesel oil used for?

It is mainly used as a fuel for lorries, buses and in some cars.

7

What is fuel oil used for?

It is a heavy fraction used as a fuel for large industrial boilers, oil-fired power stations and ships.

8

What is bitumen used for?

It's used in road combustion and waterproof roof material.

9

What is the trend in boiling points of the main fractions?

As the list goes down (refinery gases -> bitumen), the boiling points increase - bigger hydrocarbon chain length.

10

What happens to the viscosity of the main fractions?

As the list goes down, there is an increase in the size of molecule and therefore an increase in viscosity.

11

Why is carbon monoxide poisonous?

It binds to haemoglobin in blood irreversible and prevents oxygen transport.

13

What is catalytic cracking?

A way in which long-chain alkanes are connected to alkenes and shorter-chain alkanes.
• temperature at 600-700°C
• silica/alumina used as a catalyst
• pressure at 70 atmospheres

14

What happens in car engines with nitrogen and oxygen?

The temperature in car engines is high enough to allow nitrogen and oxygen from the air to react and form nitrous oxides (NO).

15

Is a catalyst used in fractional distillation or cracking?

cracking

16

Are alkenes in fractional distillation or cracking?

cracking

17

Do decomposition reactions occur in fractional distillation or cracking?

cracking

18

Are fuels obtained in fractional distillation or cracking?

both - fractional distillation and cracking

19

Is separation the main purpose in fractional distillation or cracking?

fractional distillation