Question

What is the purest form of Iron?

Answer 1

1. Purest form of Iron is Wrought Iron. It is obtained by the process of smelting.
2. Extraction of iron involves the Concentration of Iron involves processes like Roasting and Calcination. Calcination is the process in which ores are converted into oxides by means of heating in absence of air whereas, In Roasting, the ores are converted into oxides in presence of Oxygen.
3. Now, after concentration the impurities like Sulphur and Carbonates are removed, and the concentrated iron ore is with Limestone and Coke and pour into a Blast furnace.
4. It is obtained from Cast Iron in a reverberatory furnace.
   $\mathrm{IRON}\mathrm{ORE}\stackrel{\mathrm{Blast}\mathrm{Furnace}}{\to }\mathrm{PIG}\mathrm{IRON}\stackrel{\mathrm{Pudding}\mathrm{Furnace}}{\to }\mathrm{WROUGHT}\mathrm{IRON}$
5. In this process, Cast Iron is oxidized by impurities lined with Haematite ore (${\mathrm{Fe}}_2{\mathrm{O}}_3$). However, Hematite ore oxidizes Carbon to give Carbon Monoxide.
   $$\begin{gathered} {\mathrm{Fe}}_2{\mathrm{O}}_3\left(\mathrm{s}\right)+\hspace{0.17em}3\mathrm{C}\left(\mathrm{s}\right)\to 2\mathrm{Fe}\left(\mathrm{s}\right)+\hspace{0.17em}3\mathrm{CO}\left(\mathrm{g}\right) \\ \mathrm{Wrought}\mathrm{Iron} \end{gathered}$$
6. In this reaction, Limestone (${\mathrm{CaCO}}_3$) is added as a flux, and Sulphur, Silicon, and Phosphorus are oxidized and removed during the reaction.
7. Hence, the pure form of Iron that is Wrought Iron is produced.