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How do i separate gold from sulphides without using chemicals or dieing from sulpheric acid?

My freind has a large supply of microscopic gold particles, however they need to be separated from sulphides. there is a high concentration of gold in this solution, and millions of dollars could be made. however, heating the sulphides will make sulpheric acid, which burns away your lungs (also used in chemical warfare). chemicals currently used for the process of separating sulphides from gold are very toxic, and also expensive. the chemical process is very inefficient too. i am looking for a way to separate sulphides from gold without using (toxic, dangerous, expensive, rare) chemicals.

lemonie4 years ago
Can you be really specific about what this solution is and where it comes from? I might have ideas if I knew more. I'd guess that to extract a value of gold in the $millions he would have tons(literal) of the stuff? L
biolethal (author)  lemonie4 years ago
hmmmmmm.... i just got a sample of the stuff today, but i do not know the exact chemical composition of the solution. it is a very fine powder, and very heavy, meaning a high density. the solution comes from a gold mine. near the gold mine some fist sized lumps of pure platinum were found, so the powder may contain some of that. the powder is slightly corrosive, and could contain some iron. there are literally tons of the stuff. my freind tried out truck sized shaker tables, however that did not work.
OK he's got a literal gold-mine!
If it's a fine powder I guess it has been through a process already. Looking at e.g.this page I'd think that knowing the geographical location (I don't) you could find what type of ore is being mined and deduce what process it's been through. That would give you some starters on how to re-treat it?

L
biolethal (author)  lemonie4 years ago
the ore has already been mined, but much of the gold from the gold veins was left over in a dust form. this, however got mixed with sulphides. now there are still tonnes of the mixture down there, that have not been through a certain process. i think the mine is in california...
How do you know "much of the gold from the gold veins was left over in a dust form. this, however got mixed with sulphides" without knowing what process this has been through or where it was mined - If someone is telling you this much information I should think they know a bit more? Can you get hold of cyanide? L
biolethal (author)  lemonie4 years ago
I can get hold of cyanide, however this would defeat the purpose of the question... All i know about the stuff is that it has come from an abandoned mine that has been reopened, and it was abandoned because the chemical reaction to process the stuff was too costly and inefficient. however i would still like to learn about the cyanide and the chemical reaction involved in this process. thanks for the help.
See link 28-Jun and maybe plug some of those words into a search? L
that powder is corrosive and acid because of sulphates content and heavy because of iron, copper, silver, nickel and arsenic may be , I mean it should be mostly a mix iron and copper sulphates . What about the color ?
many years ago I found a litle of that stuff too I mean of sulphates ore concentrates in an abandoned and almost dismantled gold mine processing plant. I just put that green yellowish powder in an an old iron pot an roasted it on a camp fire until turned black and magnetic. I won't do that any more because generates an awful quantity of sulphur and eventually arsenic gases and actually i did not see any gold in my microscope. Before polluting the whole region or get poisoned I suggest you to professionally test the real gold content of that material. Are you sure about fist size platinum masses? Anyway platinum is much heavier than gold and more easily separable by gravity methods .
JackWayne2 years ago
Look-up Iodine leaching of Gold on the internet. Iodine is safe and reusable. Also it leaches Gold,Platinum, and silver in that order and none of the base metals. Works great on iron gossan which is what you have in your dirt.That's really a good thing because you don't have the cost to crush your ore. JackWayne Http://www.rareearthexplorationllc.com
kysar3 years ago
google " basement chemistry for the prospector " this might help.
biolethal (author)  kysar2 years ago
thanks, that link helped a lot.
kysar3 years ago
One way is heat up the material and use a magnet to remove the iron but that produces a poisonous gas. Another way I have heard of is use fertilizer mixed with the material, you must keep the material moist but not wet it must have enough oxygen for this to work. this takes some time so be patient. As I recall you need an ammonium nitrate base fertilizer. A heated rotating barrel with air vents and a water supply that would just trickle it in and keep it moist might work.
Johenix4 years ago
Quetion: Is the Iron magnetic? Try drying the powder and using a magnet. Put the magnet in a plastic bag and drag the bag over the powder.

Some sulphides (Copper Sulphide for example) are oiley and adhere to soap bubbles. Add soapy water and blow air through it. This method is used to concentrate copper sulphide ore.

Cyanide, Sodium, Potassium and Hydrogen Cyanides are quick kill poisons but are broken down by oxidation as opposed to Mercury which is an indestructable elemental slow poison. Cyanide in a fast moving stream will oxidize in one to two miles of travel.
Hydrogen Cyanide (Prussic Acid Gas) is a poisinous gas formed when a Cyanide is exposed to an acid. The stronger acid causes the Hydrogen+ and Cyanide- ions to combine into Hydrogen Cyanide and form gas bubbles. This reaction does not happen if the solution is kept Alkaline.
The gold and silver are precipitated from the solution by the addition of Zinc powder.

If you really want some books on the subject go to Lindsay Books on the web. I'm shocked they don't advertise here.
artb604 years ago
first of all, sulphuric acid would not touch the gold particles. It might dissolve some of the sulphides. you will not die from sulphuric acid, unless you handle it very carelessly. you will find it in your car battery. It can be purchased at most auto parts stores. as battery acid.. I have not run into gold sulfides, and would most likely find it to be interesting. I have found a lot of iron pyrates, or fools gold, whis is a form of iron sulfate. This will disolve in sulphuric acid.almost completely.
In the past I have reclaimed gold from old electronic equipment. There in lies a whole spectra of metals. Gold, silver platinum, pladium, copper, aluminum, tantilum and Iron. (plus a bunch of more exotic stuff in tiny amounts. in order to successfully remove the metal, and separate it, one would have to remove it selectively. Eg; sulfuric acid will dissolve copper, and not a lot of any thing else. Nitric acid will dissolve silver, aqua regia will dissolve gold, and metals in this group. the metal can be plated out of the acid and will be in a relitavely pure form. all of this is slow. it takes some times, weeks to complete the process. Cyanide is a different story. It is a bit faster, and will remove most non ferrious metals. It will even dissolve nickle, so don't use stainless steel. Cyanide however is toxic.. it is so toxic that it will kill almost every living organisim that it comes in contact with. including you. and it doesn't waste a lot of time doing it. the fumes must be collected and run through a filtering and neutralizing bed. The person handling the stuff should wear a protective suit, and have an air mask that gets its air from a remote location. The EPA and other such agencies would have a field day.
There is an alternative though. consider putting the stuff into a vaccuum oven and cook it at a temperature slightly higher than the melting point of gold.  if the sulfuric acid didn't totally disolve the sample, then it should out gas the sulphur, and leave you with a button of gold. this is a very simplistic description, but you get the idea. I did read an article some time ago where there is a strain of bacteria that will fix gold in thier bodies, and they can be smelted to recover the gold, but I have never tried this. I always just lumped all of the metal in a box and sent it to harmon and handy, NY,NY. and let them sort it out.
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