All Questions
Tagged with extraction metallurgy
13
questions
-2
votes
2
answers
289
views
What is the reason for extracting copper from copper pyrites and not iron?
Why can copper be extracted from copper pyrites ($\ce{CuFeS2}$) but not iron? Is there some intuitive logic behind it?
1
vote
2
answers
1k
views
Extraction of copper from chalcopyrite
During the extraction of copper from chalcopyrite ore, the ore ($\ce{Cu2S.Fe2S3}$) is heated to form $\ce{Cu2S}$ and $\ce{FeS}$. Then during smelting it reacts with $\ce{O2}$ to form $\ce{Cu2O}$.
Then ...
2
votes
0
answers
95
views
Why does 'softening' of lead oxidise only elements other than lead?
In a flowchart describing the steps to refine lead obtained after the reduction step, my book1 gives a short note on the process 'Softening of lead' where the crude lead is melted in the presence of ...
- 2,090
0
votes
0
answers
254
views
Difference between calcination, roasting and pyrolysis
Hie everyone. I have been going through pyrometallurgical processes for recycling lithium-ion batteries and l have been coming across these terms; calcination, pyrolysis and roasting which l need ...
2
votes
1
answer
661
views
Use of Spiegeleisen in manufacture of steel
I recently read the following statements related to Manufacture of steel via Bessemer Process:
When no more $\ce{CO}$ is produced (i.e. blue flame disappears) a calculated amount of Spiegeleisen (...
- 1,350
8
votes
1
answer
631
views
Need of refining aluminium and Hoope vs Hall–Héroult processes
Recently I was taught how aluminium is commercially extracted. The ore is first concentrated by leaching either by Bayer's process for red bauxite (impurity: $\ce{Fe2O3}$) or by Serpeck's process for ...
- 1,169
0
votes
0
answers
30
views
Separation of Al-Si alloys without electrolysis
Can pure (or roughly pure) $\ce{Al}$ be somehow thermally, chemically, or physically separated from the $\ce{Si}$ contained in an $\ce{Al-Si}$ alloy? How? Approximately what purity of Aluminum can be ...
- 313
1
vote
1
answer
3k
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Why do we use coke instead of coal in order to reduce FeO as basic reaction in ironmaking process?
Why is coke used as a reducing agent to reduce FeO to produce iron instead of coal.I admit that coke is carbonaceous but what is it that compels us to use coke instead of the naturally available coal?
- 372
7
votes
2
answers
6k
views
Why is ZnO reduced in this reaction?
Consider the following Ellingham diagram.
At 673K, the Gibbs energy value of oxidation of Zn is more negative than the Gibbs energy value of oxidation of C (coke). So, Zn should be oxidised to ZnO. ...
- 567
3
votes
1
answer
630
views
Zinc Sulfate Purification
In the process for electrolysis for zinc, three things must be done:
Leaching the ZnO
Purifying the ZnSO4 by means of cementation
Performing the electrolysis
However, step 2, as it is presented by ...
- 133
6
votes
2
answers
4k
views
Froth floatation process - why CuSO4 is activating floating character of ZnS?
I read the following :
"In a mixture of $\ce{PbS}$, $\ce{ZnS}$ and $\ce{FeS2}$, each component is separated from each other in froth floatation process by using the reagents potassium ethyl ...
- 1,439
8
votes
3
answers
8k
views
When is Serpeck's process preferred over Bayer's process?
Both these processes are used in concentration of bauxite.
They use different reagents.
Which is more commonly used (wikipedia says Bayer's) and why?
When is one preferred over the other?
Which is ...
- 97
18
votes
4
answers
3k
views
What possibilities are there for refining aluminium on the moon?
Engines burning aluminium and liquid oxygen have been investigated for use on the moon because there is plenty of both elements in the soil - about 13% and 40% of highland soil, respectively. ...
- 533