Test your knowledge with free interactive questions on Seneca — used by over 10 million students.

Extracting Iron (Blast Furnace)

A blast furnace is an industrial reactor that is used to extract iron from its ore (called haematite). The extraction of iron from its ore uses the principle of reduction reactions. Oxygen is removed from iron using the more reactive carbon.

Carbon dioxide formed

Carbon dioxide formed

  • Iron ore, limestone and coke (carbon) are fed into the top of the blast furnace.
  • Hot air is blasted in from the bottom.
  • The carbon reacts with the oxygen to form carbon dioxide and a lot of heat.
    • C(s) + O2(g) → CO2(g)
  • This reaction is exothermic and provides the high temperature that the other reactions need.
Carbon monoxide formed

Carbon monoxide formed

  • The carbon dioxide reacts with more coke higher up the blast furnace. Carbon monoxide is formed.
    • C02 + C(s) → 2CO(g)
  • This reaction is endothermic.
Molten iron formed

Molten iron formed

  • The haematite is reduced by the carbon monoxide to molten iron.
    • Fe2O3(s) + 3CO(g) → 2Fe(l) + 3CO2(g)
Limestone decomposes

Limestone decomposes

  • Limestone is added as a cleaning agent to react with acidic oxides (Al2O3 and SiO2) impurities.
  • The limestone decomposes because of the high temperatures.
    • CaCO3 → CaO(s) + CO2(g)
Molten slag formed

Molten slag formed

  • The calcium oxide reacts with silicon(IV) oxide, which is one of the main impurities in the blast furnace.
  • This reaction forms calcium silicate, which forms a layer of slag above the molten iron.
    • CaO(s) + SiO2(s) → CaSiO3(l)
Uses

Uses

  • Slag is used in road and rail construction.
  • The iron produced is called pig/cast iron. Most pig iron is turned into steel.
Jump to other topics
1

States of Matter

2

Atoms, Elements & Compounds

3

Stoichometry

4

Electrochemistry

5

Chemical Energetics

6

Chemical Reactions

7

Acids, Bases & Salts

8

The Periodic Table

9

Metals

10

Chemistry of the Environment

11

Organic Chemistry

11.1

Formulae, Functional Groups & Terminology

11.2

Naming Organic Compounds

11.3

Fuels

11.4

Alkanes

11.5

Alkenes

11.6

Alcohols

11.7

Carboxylic Acids

11.8

Polymers

12

Experimental Techniques & Chemical Analysis

Practice questions on Extracting Iron

Can you answer these? Test yourself with free interactive practice on Seneca — used by over 10 million students.

  1. 1
  2. 2
    Blast FurnacePut in order
  3. 3
  4. 4
  5. 5
Answer all questions on Extracting Iron

Unlock your full potential with Seneca Premium

  • Unlimited access to 10,000+ open-ended exam questions

  • Mini-mock exams based on your study history

  • Unlock 800+ premium courses & e-books

Get started with Seneca Premium