The key difference between carbon reduction and thermite process is that in carbon reduction, we can extract a base metal from its ore via reduction of fused metal oxide using carbon whereas, in thermite process, we use aluminium powder instead of carbon.
Carbon reduction and thermite process are two important metallurgical processes. Therefore, we use these processes mainly in industrial needs. The carbon reduction is a step of smelting; in smelting, we apply heat to a metal ore in the presence of a reducing agent, which is carbon. However, in the thermite process, we do the same process with aluminium powder instead of carbon.
CONTENTS
1. Overview and Key Difference
2. What is Carbon Reduction
3. What is Thermite Process
4. Side by Side Comparison – Carbon Reduction vs Thermite Process in Tabular Form
5. Summary
What is Carbon Reduction?
Carbon reduction is a process from which we can extract a metal from a fused metal oxide using carbon. Here, carbon acts as a reducing agent. In this process, we can get free metal out of metal oxide in the ore. Further, this method is suitable for metals such as iron, copper, zinc, etc.
Figure 01: A Smelter Uses the Carbon Reduction Method for the Extraction of Metals
In this process, first, we need to mix the roasted or calcined ore with a suitable quantity of coke or charcoal (coke and charcoal are the best sources of carbon). Then, we need to apply heat. It requires a very high temperature. It will eventually decompose the metal ore by removing other chemical elements as gases or slag (glass-like byproducts) and leaves the metal behind in free form. Mainly, we need to carry out this process in a blast furnace in the presence of a controlled supply of air. If we are going to isolate the metal zinc from its ore, the carbon reduction reaction is as follows:
ZnO + C ⟶ Zn + CO
Additionally, we need to add an additional reagent to the ore to remove the impurities still present in the ore. We call it “flux”. Further, this flux can combine with the impurities and form a fusible product; we call this “slag”.
What is Thermite Process?
Thermite process is a technique in which we can extract a metal from its ore using aluminium powder. Also, this process reduces the metal oxide into free metal. The reducing agent is aluminium.
Moreover, the major metals we can extract from this method are chromium and manganese. We can do this because aluminium is more electropositive than chromium and manganese. The chemical reactions for this process are as follows:
2Al + Cr2O3 ⟶ Al2O3 + 2Cr
8Al + Mn3O4 ⟶ Al2O3 + 9Mn
What is the Difference Between Carbon Reduction and Thermite Process?
Carbon reduction and termite process are two types of techniques we can use to isolate a metal from its oxide compound. The key difference between carbon reduction and thermite process is that in carbon reduction, we can extract a base metal from its ore via reduction of fused metal oxide using carbon whereas, in thermite process, we use aluminium powder instead of carbon.
When considering their reaction principles, the difference between carbon reduction and thermite process is that in carbon reduction, carbon passes its charges to the metallic cation, changing the charge of the metal from positive to zero. Thus, we can obtain free metal eventually. In the thermite process, aluminium is more electropositive than chromium and manganese; thus, it can replace the metal in the oxide compound. Examples for metals we can extract from the carbon reduction process includes zinc, copper, iron, etc., while chromium and manganese are the metals we can extract from the thermite process.
Summary – Carbon Reduction vs Thermite Process
Carbon reduction and termite process are two types of techniques we can use to isolate a metal from its oxide compound. In summary, the key difference between carbon reduction and thermite process is that in carbon reduction we can extract a base metal from its ore via reduction of fused metal oxide using carbon whereas, in thermite process, we use aluminium powder instead of carbon.
Reference:
1. “Metals and Metallurgy.” LinkedIn SlideShare, 15 Jan. 2018, Available here.
Image Courtesy:
1. “Houghton Michigan UpperPeninsula” By Wolpodzilla – Own work (Public Domain) via Commons Wikimedia
2. “thermite reaction” By User:Nikthestunned (Wikipedia) – Own work – also at Flickr (CC BY-SA 3.0) via Commons Wikimeida