Outcomes:
> to compare the methods used to obtain copper from low-grade ores.
Extracting copper from low-grade copper ores
Instead of extracting copper from our limited copper-rich ores, scientists are developing new ways to get copper from low-grade ores. This would be uneconomical using traditional methods. We can now use bacteria (bioleaching) and even plants (phytomining) to help extract copper.
Both of these methods can then use displacement by scrap iron and electrolysis to extract pure copper metal.
Summary questions
1 Why is copper an important metal in our technological society?
2 a Explain briefly two traditional ways of extracting copper metal.
b State an advantage of extracting copper using bacteria rather than traditional methods.
c Why can copper occasionally be found native?
d When copper is purified by electrolysis, which electrode do you think the pure copper collects at? Explain your answer.
3 Write a balanced chemical equation, including state symbols, for the extraction of copper:
a from copper(II) sulfide by smelting (reduction)
b from copper(II) sulfate solution by displacement
4 a write ionic half equations for the reactions at each copper electrode in the electrolysis of copper(II) sulfate solution.
b Explain where reduction and oxidation takes place in the electrolysis cell in part a.
5 Explain how copper is extracted by phytomining and why this method will become increasingly important.
BBC Bitesize: The future of copper