Chemical Forums

Please login or register.

Login with username, password and session length

Sponsored links

Pages: [1] 2   Go Down

Author Topic: Extracting Gold, Silver, Copper from ore  (Read 23803 times)

0 Members and 1 Guest are viewing this topic.

geubrina

  • Regular Member
  • ***
  • Mole Snacks: +1/-1
  • Offline Offline
  • Posts: 11
Extracting Gold, Silver, Copper from ore
« on: January 16, 2008, 07:05:27 PM »

Hi, anybody can help me so I can demonstrate of how to extract copper ore. As the Lab result, the ore has copper, gold and silver content.

Logged

LQ43

  • Chemist
  • Full Member
  • *
  • Mole Snacks: +32/-9
  • Offline Offline
  • Gender: Female
  • Posts: 250
Re: Extracting Gold, Silver, Copper from ore
« Reply #1 on: January 19, 2008, 05:31:03 PM »

Google "extracting copper from ore"
« Last Edit: January 20, 2008, 05:11:24 AM by LQ43 »
Logged

hmx9123

  • Retired Staff
  • Full Member
  • *
  • Mole Snacks: +59/-18
  • Offline Offline
  • Posts: 887
Re: Extracting Gold, Silver, Copper from ore
« Reply #2 on: January 25, 2008, 09:19:57 PM »

It's generally done with cyanide now a days.  I wouldn't want to do that.
Logged

Alpha-Omega

  • Full Member
  • ****
  • Mole Snacks: +359/-231
  • Offline Offline
  • Gender: Female
  • Posts: 700
  • Physical Inorganic Chemist
Re: Extracting Gold, Silver, Copper from ore
« Reply #3 on: January 26, 2008, 10:43:58 AM »

The above response is accurate and correct.  However, you could use this process (no cyanide-sulfuric acid and zinc chloride) as demonstrated at this link:

Nice step-by-step extraction procedure with animation that demonstraes the analytical techniques:

http://ch185.semo.edu/copper/lab6intro.html

This will give you your copper...


Thiosulphate leching is anoter method: 

http://sci.ege.edu.tr/~jfs/chem/06/Silver_Extraction_from_Argentite_by_Thiosulphate_Leaching.pdf
« Last Edit: January 26, 2008, 11:59:53 AM by mebecker1 »
Logged

THC

  • Full Member
  • ****
  • Mole Snacks: +4/-6
  • Offline Offline
  • Posts: 132
Re: Extracting Gold, Silver, Copper from ore
« Reply #4 on: January 27, 2008, 07:43:10 AM »

This is maybe completely off, but my teacher talked about elektrochemistry in this context? You make a elektrochemical cell with Cu2+ on your ore in half-cell and another more noble metal + ions in the other half-cell.
Logged

Arkcon

  • Global Moderator
  • Sr. Member
  • ***
  • Mole Snacks: +336/-112
  • Offline Offline
  • Posts: 4812
Re: Extracting Gold, Silver, Copper from ore
« Reply #5 on: January 27, 2008, 07:50:42 AM »

This is maybe completely off, but my teacher talked about elektrochemistry in this context? You make a elektrochemical cell with Cu2+ on your ore in half-cell and another more noble metal + ions in the other half-cell.

True enough, the final step in the purification of copper for especially electrical use is electrochemical.  More noble impurities accumulate as an anodic slime.  The input copper for electrorefining is usually >99%, however.
Logged
That all depends on how reasonable we're all willing to be.  I just want my friends back, except for Cartman, you can keep him.

Arkcon

  • Global Moderator
  • Sr. Member
  • ***
  • Mole Snacks: +336/-112
  • Offline Offline
  • Posts: 4812
Re: Extracting Gold, Silver, Copper from ore
« Reply #6 on: January 27, 2008, 08:10:20 AM »

'Course, if you're bored with mundane chemical purification, there's always bacterial methods {clicky}
Logged
That all depends on how reasonable we're all willing to be.  I just want my friends back, except for Cartman, you can keep him.

geubrina

  • Regular Member
  • ***
  • Mole Snacks: +1/-1
  • Offline Offline
  • Posts: 11
Re: Extracting Gold, Silver, Copper from ore
« Reply #7 on: March 21, 2008, 07:23:55 PM »

Hi everybody, I found out that there is magnetic element in the ore, so I heated the pulverized ore and then manually remove it with magnet.
The leftover should be minus iron/nickel content, right?

Then can I proceed with the aqua regia?
Logged

Arkcon

  • Global Moderator
  • Sr. Member
  • ***
  • Mole Snacks: +336/-112
  • Offline Offline
  • Posts: 4812
Re: Extracting Gold, Silver, Copper from ore
« Reply #8 on: March 22, 2008, 12:12:08 AM »

If you add conc. sulfuric acid, with either air or oxygen gas bubbling, you can quantitatively react the copper, leaving more noble metals behind.  Aqua regia will simply dissolve everything (usually), once you've done that, then what will you do?
Logged
That all depends on how reasonable we're all willing to be.  I just want my friends back, except for Cartman, you can keep him.

geubrina

  • Regular Member
  • ***
  • Mole Snacks: +1/-1
  • Offline Offline
  • Posts: 11
Re: Extracting Gold, Silver, Copper from ore
« Reply #9 on: March 22, 2008, 06:02:58 AM »

If you add conc. sulfuric acid, with either air or oxygen gas bubbling, you can quantitatively react the copper, leaving more noble metals behind.  Aqua regia will simply dissolve everything (usually), once you've done that, then what will you do?

You said I can react the copper quantitatively; is that mean not all the copper but most of the copper will react? As per your prediction, how much of the copper will be left behind?

Regarding the Ag and Au, I think Ag is more reactive to HCl compare to Au, so, maybe I will put the left behind metals into HCl slowly and let the Ag react first with the HCl. And maybe, I have to wash this several times.

After that, what should I do with the left behind Au?
Logged

Arkcon

  • Global Moderator
  • Sr. Member
  • ***
  • Mole Snacks: +336/-112
  • Offline Offline
  • Posts: 4812
Re: Extracting Gold, Silver, Copper from ore
« Reply #10 on: March 22, 2008, 06:39:30 AM »

You said I can react the copper quantitatively; is that mean not all the copper but most of the copper will react? As per your prediction, how much of the copper will be left behind?

No, that means over time, all of it does, and the soluble portion is valid for quantitative analysis for copper.

Quote
Regarding the Ag and Au, I think Ag is more reactive to HCl compare to Au

Really?  Pure solid silver is going to react with hydrochloric acid, to produce solid, insoluble silver chloride, which will shield the mass from further action.

This is a common beginners problem with quantitative ore analysis.  The beginner attitude of "I'm just going to soak it all in aqua regia, the strongest acid of all, and all that I want will dissolve." doesn't always work.  Conc. nitric doesn't always work -- it may passivate ferrous alloys, blocking further reactions.  Hydrochloric may form an insoluble crust with silver, lead, and mercury, even as other reagents reduce them to free metals.  Since aqua regia is both, either or both effects (or perhaps neither -- like I said it may work) may occur.  Your ore sample may require pre-digestion with hydrofluoric acid to dissolve enough of the rocky matrix, even though hydrofluoric is a weak proton donor.  You should be able to read up on these particular topics in ore processing for quantitative analysis and the need for these procedures.

There are other metallurgical manipulations for you to review, cupelation is still practiced, electro-refining has been mentioned before in this tread.  As has cyanidation, and I threw in bioleaching just for the fun of it.
Logged
That all depends on how reasonable we're all willing to be.  I just want my friends back, except for Cartman, you can keep him.

geubrina

  • Regular Member
  • ***
  • Mole Snacks: +1/-1
  • Offline Offline
  • Posts: 11
Re: Extracting Gold, Silver, Copper from ore
« Reply #11 on: March 22, 2008, 03:13:02 PM »

Anyway, I think I have get rid off 2 element which is not gold or silver.
First by magnet, I have take out the iron, and
Second, the copper.

Now, how do I separate the gold and silver? I read that use the salt, I can make the agcl?
If possible, than only the gold is left.
Logged

geubrina

  • Regular Member
  • ***
  • Mole Snacks: +1/-1
  • Offline Offline
  • Posts: 11
Re: Extracting Gold, Silver, Copper from ore
« Reply #12 on: March 24, 2008, 04:09:05 AM »

Arkon, maybe after taking out the Copper by Sulphate acid, I should decant and wash the remain until clean. Then I should put the HNO3, you know to dissolve any metal but the noble one.

Then decant the solution again and use the AR.

Pls tell me is this theoretically, right?
Logged

Arkcon

  • Global Moderator
  • Sr. Member
  • ***
  • Mole Snacks: +336/-112
  • Offline Offline
  • Posts: 4812
Re: Extracting Gold, Silver, Copper from ore
« Reply #13 on: March 24, 2008, 04:42:50 AM »

Well done, that was the systematic method that I wanted you to develop:
1). Grind to a powder
2). Magnetic separation
3). Sulfuric acid extraction
4). Nitric acid extraction
5). Aqua regia extraction.

Will you quantitate each fraction chemically, or by AA (flame or ICP)?  Or will you simply dry and mass?  Or reduce the soluble components to free metal.  In that case, typically, cupellation is what's done to ores, why have you excluded this?  Or is that not your ultimate goal?  Like I told you months ago -- http://www.chemicalforums.com/index.php?topic=21751.msg83169#msg83169
people hardly ever do this by wet chemical or metallurgical means, anymore.  Unless they're panning/mining for gold in some Alaskan or Siberian homestead.  But even those places are moving towards cyanidation processes.

*[EDIT]*
my misspelling cupell probably screwed up your Google searches, srry
« Last Edit: March 24, 2008, 05:06:35 AM by Arkcon »
Logged
That all depends on how reasonable we're all willing to be.  I just want my friends back, except for Cartman, you can keep him.

geubrina

  • Regular Member
  • ***
  • Mole Snacks: +1/-1
  • Offline Offline
  • Posts: 11
Re: Extracting Gold, Silver, Copper from ore
« Reply #14 on: March 28, 2008, 04:59:46 AM »

Well done, that was the systematic method that I wanted you to develop:
1). Grind to a powder
2). Magnetic separation
3). Sulfuric acid extraction
4). Nitric acid extraction
5). Aqua regia extraction.

Will you quantitate each fraction chemically, or by AA (flame or ICP)?  Or will you simply dry and mass?  Or reduce the soluble components to free metal.  In that case, typically, cupellation is what's done to ores, why have you excluded this?  Or is that not your ultimate goal?  Like I told you months ago -- http://www.chemicalforums.com/index.php?topic=21751.msg83169#msg83169
people hardly ever do this by wet chemical or metallurgical means, anymore.  Unless they're panning/mining for gold in some Alaskan or Siberian homestead.  But even those places are moving towards cyanidation processes.

*[EDIT]*
my misspelling cupell probably screwed up your Google searches, srry

Arkon, what will happen if we switch the no.3 and no.4 step?
Logged
Pages: [1] 2   Go Up
 

Mitch Andre Garcia's Chemical Forums 2003-Present.

Page created in 0.115 seconds with 23 queries.