Question

Which of the following reaction involved in extraction of copper from chalcopyrite?

• A. $FeO+Si{O}_2\to FeSi{O}_3\text{(slag)}$
• B. $2C{u}_{2}O+C{u}_{2}S\to 6Cu+S{O}_2$
• C. $FeO+CO\to Fe+2CO$
• D. $2C{u}_{2}S+3O_2\to 2C{u}_{2}O+2S{O}_2$

Answer 1

Answer: (A), (B), (D)

$2C{u}_{2}S+3O_2\to 2C{u}_{2}O+2S{O}_2$

The chalcopyrite ore is $CuFe{S}_2$. The concentrated copper oxide ore from roasting method will have iron impurities.
Roasting:
$2C{u}_{2}S+3O_2\to 2C{u}_{2}O+2S{O}_2$

The concentrated ore is mixed with silica and heated in reverberatory furnance to get copper matte.

Copper matte is charged with silica lined convertor with addition of some silica followed by hot air blast to convert remaining $FeS,FeO$ and $C{u}_{2}S/C{u}_{2}O$ to $Cu$.

$2FeS+3O_2\to 2FeO+2S{O}_{2}FeO+Si{O}_2\to FeSi{O}_3\text{(slag)}2C{u}_{2}O+C{u}_{2}S\to 6Cu+S{O}_2$

Iron oxide is removed as slag in this extraction.
Hence, option (a), (b) and (d) are correct.