Extraction of Crude Metal from Concentrated Ore


Table of Content

What is Crude Metal?

The ore is considered as crude metal. It is a solid mass from which pure metal can be obtained.

Steps for Extraction of Metal

Extraction of metals involves three major steps:

Isolation of metal from the concentrated Ore involves the refining of metals from the compounds. The first step is to convert an ore into an oxide. Then the oxide is reduced using a reducing agent. 

Conversion to Oxide- Metal refining is done by heating the ore in a limited supply or absence of oxygen.  For example, hydrated ferric oxide is heated to form dry ferric oxide.

Fe2O3.xH2O(s)  → Fe2O3 (s) + xH2O(g)

Fig. 1. Equation of conversion ore to oxide

Roasting- During this process, extraction is done by heating the ore in a regular supply of air.  Sulphide ores of elements such as Zinc, Lead and Copper are treated and concentrated using this methodology. The sulphur in the ore, at high temperature reacts with the oxygen to form Sulphur Dioxide and escapes out.

2ZnS      +    3O2         →     2ZnO + 2SO2

Fig. 2. Roasting

Reduction of Oxide to Metal – It is a process of removal of oxygen. Generally, reducing agents such as carbon or carbon monoxide is used in this step. Carbon is added to the metal oxide obtained from the ore and then heated.

MxOy + yC → xM + y CO

Ellingham Diagram

It is a graphical representation of Gibbs energy. These diagrams are used for finding the choice of reducing agent in the reduction of the oxides. These are used to find out the feasibility of thermal reduction of an ore. 

Ellingham Diagram

Fig. 1. Ellingham Diagram

Limitations of Ellingham Diagram

  • It does not give any information regarding the kinetics of the reduction process.

  • These diagrams believe that reactants and products are in equilibrium, but this is not always the case.


The process of heating in limited supply or absence of air is known as calcination.

Examples of calcination processes include the following:

Watch this Video for more reference

More Readings

Extraction of Crude Metal from Concentrated Ore


Upto 50% Scholarship on Live Classes

Course Features

  • Video Lectures
  • Revision Notes
  • Previous Year Papers
  • Mind Map
  • Study Planner
  • NCERT Solutions
  • Discussion Forum
  • Test paper with Video Solution