laughgddd
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extracting copper
how can i extract copper metal from the ore contains a mixture of CuCO3 and Cu(OH)2 ,in a most effective way and with the lowest amount of money?
i was given
1L dilute sulphuric acid
100g zinc powder
100g carbon powder
100g magnesium ribbon
it is a school project.please help me!!!thanks
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laughgddd
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1L dilute sulphuric acid $4
100g zinc powder $17
100g carbon powder $12
100g magnesium ribbon$120
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12AX7
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A quick Google search returns several sites containing information on the "wet" extraction method.
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darkflame89
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Place your mixture into the dilute sulphuric acid, wait for everything to dissolve into the acid. By then, you would have a blue/green solution. Add
zinc powder into the solution. Copper metal will 'precipitate' out of the solution.
Ignis ubique latet, naturam amplectitur omnem.
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unionised
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It's bad enough giving people an answer to their homework questions but it's worse if you don't get the right answer.
This bit of the question
"in a most effective way and with the lowest amount of money?"
seems to have been ignored.
What laughddd needs to do is work out how much of each of those reducing agents it would take to produce some amount of copper - say a kilogram- then
see which is cheapest.
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Ephoton
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Mood: trying to figure out why I need a dark room retreat when I live in a forest of wattle.
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use Al for your reduction heaps cheaper than Zn or an electrolitic method
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laughgddd
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one thing..
heating may also include..
but it is expensive
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darkflame89
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Huh? What's wrong? Zn and Mg will both reduce the same amount of copper. But Zn is much cheaper than copper and zinc does its job well. On the other
hand, magnesium has a small side reaction that causes you to waste some magnesium. That small side reaction is magnesium reacting with water.
Carbon is cheaper than zinc, yes but you have to heat it. Not only that, you will spend quite some time heating it. And after that, you will have to
distill the zinc vapor that comes out. (Search "zinc industrial production by carbon reduction") This is not reduction of lead ore where the lead
globules are easily consolidated.
The question says most effective and cheapest way to extract copper. If time is money, and effort is money, than zinc is a best for all you have to do
is to put the zinc metal into the solution of copper(II) ions as you spent the least effort. Trading off $5 for the time and effort is quite worth it.
Ignis ubique latet, naturam amplectitur omnem.
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praseodym
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Yup, and the reaction is not too difficult to do since the displacement reaction between zinc metal and copper (II) ions occurs quite readily.
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unionised
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OK, I'm making an assumption here. While the question is set in an accademic situation I think the idea is to introduce the students to the ideas of
comercial ecconomics. I think that's a reasonable assumption- why else would they be asking about cost? So I think this should be looked on as a large
ccale reaction- tons of materials rather than a few grams.
If I'm wrong about that then some (but not all) of the following comments don't make sense.
"Huh? What's wrong"
Just about everything that you have said.
"Zn and Mg will both reduce the same amount of copper"
This would be true if their equivalent weights were the same, but in the real world a gram of Zn will produce 24.3/65.4 times as much copper as a gram
of Mg.
"Carbon is cheaper than zinc, yes but you have to heat it. Not only that, you will spend quite some time heating it. And after that, you will have to
distill the zinc vapor that comes out. (Search "zinc industrial production by carbon reduction") This is not reduction of lead ore where the lead
globules are easily consolidated. "
WTF are you on about distilling zinc for? 
Roast Co(OH)2 and/ or CuCO3 with C and you get copper- it's not rocket science; more like bronze age technology.
You mention consolidating the product- electrolysis might do that but I'm not sure that's in the spirit of the question.
Otherwise you have to heat the copper up to melt it into anything useful.
If you have to heat it anyway, you might as well use the cheapest (per mole) reducing agent which is carbon.
Of course, the really neat bit is that the reaction is exothermic so, if you could set this up as a commercial process you would have a furnace with
ore and coke going in at the top and molten copper coming out of the bottom. OK, that probably wouldn't quite work in practice but it would be easy
enough to use a blast furnace and burn excess C to produce the heat.
Your assertion that "all you have to do is to put the zinc metal into the solution of copper(II) ions" is bizare- you don't have a solution of copper
ions (and praseodym seems to be under the same delusion). To get that you would need to mess about with the acid (and pay for it). You would also have
to get rid of the ZnSO4 solution and pay disposal costs if this were a commercial process, and if it isn't then why are we wondering about costs.
You also say that "Trading off $5 for the time and effort is quite worth it. "
If we are talking about a small scale one-off reaction in the lab that might be valid, but for real ore smelting the work is done on a multi kilotonne
scale the 5$ soon adds up to a lot. Of course, if it's a lab scale experiment then the time doesn't really cost anything so the cheapest reductant
wins out anyway.
I think I will join you in being too lazy to actually work out the proportions of the chemicals and point out that you lose 4 of those 5$ paying for
the acid.
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12AX7
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Economics of copper production aren't quite usual, anyway. Copper is pretty expensive (what, $2.29/lb? ) and purity is important (the prime use being electrical conductor) so electrolytic refinement is a common step.
Electrowinning is also used.
Although zinc production involves distillation, zinc metal is cheaper than aluminum, which is already pretty cheap.
Tim
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darkflame89
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LOL, if you are talking in the economic sense, then yes, your words make sense.
Ignis ubique latet, naturam amplectitur omnem.
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unionised
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Whatever sense I'm talking in, a gram of Mg does better job (ie gives more Cu) than a gram of Zn. And I'm still wondering about the possible
relevance of distilling zinc (Except, as 12AX7 says- just to show that it's not actually that expensive a process). Please enlighten me.
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darkflame89
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There are 2 ways of winning pure zinc from its ore. Firstly, by electrochemical way(plating the zinc out of its solution).
Secondly, by reduction with carbon. In the older times, before the advent of cheap electricity, carbon was used to reduce zinc ore. The temperatures
used were high enough to cause zinc to vaporise, and the resulting zinc vapor was condensed and collected. The whole process was done in a retort.
Later, someone upscaled it into an industrial process, but the method remained pretty much the same.
For reference, check the link: http://www.iza.com/zwo_org/Basics/0202.htm
Ignis ubique latet, naturam amplectitur omnem.
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laughgddd
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but now i need to extract pure copper@@""
not zinc..
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unionised
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I understand that; some of the others here seem to be struggling with that concept.
Does the context of the question make it clearer if this is a small scale one-off reaction or a question about how you would do it on a large scale ie
industrially?
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