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Recovering gold from mud and melted steel
Q. Dear Sir:
Please Give us correct reply, then I have to recover valuable 116 gram gold from mud and melted steel.
I am doing some gold plating works in India.
When I was preparing gold plating bath first time in life, some fault happened.
162 gram gold was spoiled. When we put gold in hydrochloric acid and nitric acid {3:1} and it was boiled in a STEEL BASIN ON GAS STOVE but it was overflowed in to earth and sand and the STEEL BASIN IN WHICH WE WERE BOILING THE GOLD WITH HCl AND NITRIC ACID WAS MELTED WITH GOLD
We took the earth and sand with care fully and keep in one basin and in other basin we keep the balance melted gold water and steal. {3:1 HCl +nitric}
How we can separate the gold from the earth and mud sand and how we can RECOVER the gold from melted steal gold water. {It has became now 5 liter gold and steel water}
Can anyone give the correct methods to recover gold from mud and melted steal gold water?
WE ARE WAITING FOR THE REPLY FROM READERS OF FINISHING.COM
AFTER THAT WE HAVE TO RECOVER THE VALUABLE GOLD FROM MUD AND MELTED STEEL
Thanking you,
Babu T.K- India
Q. Please give us the recovery of metal from soil. I also did same mistake. I am also keeping the soil with gold in my workshop please give us advice.
David- Cochin, India
I know you don't think it is very funny, but BUTTERFINGERS!:-)
Tom Pullizzi
Falls Township, Pennsylvania
A. Man! You folks need a real chemist. I am certainly NOT one! Somewhere I read that gold miners in S.America have used mercury to extract their gold. The point was that the method was HIGHLY TOXIC and that they were getting heavy metal poisoning by doing it. That seems to be a method to extract it from dirt/ore. How you extract gold from an alloy, I have no idea! But if there is a place to find it on the web, I would search under "gold plating solution recovery" and see what that turned up.
Ronna E.- Amherst, Massachusetts
A. Hi...
First of all you have to be very careful while dealing with Gold dissolving as it involves deadly acid as well as costly metal (Gold), any wrong move can cause damage to your body as well as your Pocket(money). So My best advice is to take all necessary precaution and get better practice before doing it alone.
Any way I know few methods and I believe this should be helpful to you in recovering the gold from mud/steel etc. Kindly take necessary safety precautions and be mentally conformable while doing the recovery. Don't be hasty and end up in mess.
"Recovery and Refining Of precious Metals"
by C.W. Ammen
on
AbeBooks
or
eBay
or
Amazon
(affil links)
"Recovering Precious Metals"
by George E. Gee
from AbeBooks
or
Amazon
(affil links)
Method 1:
1. Prepare aqua regia 3:1 HCl and HNO3 Solution. You may prepare one liter or more according to the amount of gold you have with you.
2. Use a glass beaker [beakers on eBay or Amazon] (don't use steel or SS vessel aqua regia can dissolve that). Pour the aqua regia into it along with the gold. Bring it to boil. Lot of fumes will be evolved during the boiling process. Its better you boil it under hood or better to have a fume exhaust.
3. Boil it till the gold is completely dissolved. You will find no more gold. (no fumes)
4. Allow the solution to cool. This may take a long time. Be patient.
5. When it has cooled down. Add water to the aqua regia to dilute it. This depends on the size of beaker you have.
6. Ensure that the solution has cooled down well. Now add ammonia [on eBay or Amazon] to the solution. If the gold has contained copper / Nickel the solution will turn blue. And the iron starts to float as a brown color mass. The Gold will form Fulminate and settle down. (slightly yellow in color)
7. You can remove the floating iron and Filter the Gold fulminate with the help of 41 Whatman filter.Once the fulminate is collected on the filter paper rinse the fulminate with hot Distilled water till all the solution left in the fulminate is washed out. Don't let the fulminate to dry out it will turn into a explosive when dried. Always keep it wet. This process will take lot of time be patient and cool.
8. Ensure that the fulminate is rinsed thoroughly. Take the filter paper and dissolve in KCN Solution(Potassium cyanide). The fulminate will dissolve completely in the solution. You can remove the filter paper. (Don't forget to rinse it .. it may contain trace of gold)
9. You can use this solution for plating or if you want the gold you can either plate it out or reduce the gold using Zinc granules or zinc dust [on eBay or Amazon] .
10. You can also try some organic reducing agents. Its better you can reduce it using Zinc granules.
Method 2:
1. Prepare a Solution of KCN and put the gold mixture (better make the mass into a powder by pulverizing them) in them and allow to slowly dissolve in them. This takes a long time. I have heard that the miners use cyanide ponds to dissolve gold from the ore.
2. Once the metals dissolve in solution then you can recover them by reduction process or plate out from them using a gold cathode and SS anode.
The above methods involve time, Skill, temperament, Practice, Knowledge of chemistry and lots of patience. I have let you know what I have with me. If you still need more precise details probably you need to read some literature or refer some one before doing this. If you are doing the above you are doing at your own risk.
You can also try different combinations of above methods or different methods which ever is safe and less costly.
Good luck.....
Karthik- Singapore
A. Hi..
This is just a follow up for my previous posting. Instead of directly going for the two process I have described you can remove the contaminants one by one by using different acids like Nitric and next step you can use HCl to remove the other impurities (Iron, copper etc..these acid when used separately doesn't attack gold.. ) and finally try the purification process I have given above. Hope you will frame a process step by step such a way that it removes all contaminants and then you can go for purification of gold removing the trace contaminants. Please be careful on which vessel to use (Don't make mistake by using steel vessel or metal vessel.. better use glass beaker).
Good luck ..
Karthik- Singapore
A. Boiling the solution to HCl and nitric over. Add Sodium Metabisulfite, 1 ounce to each 1 ounce of gold. Will decant a mud, wash with water, furnace. Metal gold.
Wander- Rio de Janeiro - Brazil
A. Granulate as fine as possible or flatten as thin as possible. Burn with lighter fluid or mentholated spirit to burn off any organic matter it may have collected. Place into a heat proof (borosilicate) glass container and cover with 1 part sulfuric Acid to 10 parts distilled water. Leave this until the iron has dissolved into Iron Sulphate. It will be quicker if you can keep the temperature above 25 °C. You should then be able to pan or wash out the dirt and any left over organic particles. Don't worry about the sand, it won't affect the next step. Dissolve the remainder along with 60 grams of metallic copper or copper oxide(ii) in Aqua regia (AR). When the reaction has finished filter the liquid out and dilute with 3 times the volume of tap water. Dissolve an amount of Sodium Metabisulfite 10% more than the weight of gold expected into a cup of hot water. Pour this slowly into the diluted AR mix whilst stirring. Let settle 24-48 Hrs and then filter. Dry the sludge and then melt. BINGO! Gold....
Rusty
- NSW. Australia
July 18, 2008
A. Lye dissolves dirt; old miners would use this method to separate dirt from gold. They also add mercury then nitric acid to remove silver, copper, and iron. You don't need to use this old lye/mercury/nitric acid miner method. Sounds like you should use a strong liquid lye acid to dissolve the dirt then after filtering out the dirt put the gold mud into a clean glass container (or thick plastic container, 5-gallon bucket is perfect), add a strong mixture of ammonium chloride in water -- how ever much to cover the mud by an inch or so. Stir. If water turns green or blue, the gold's impure. Filter the mud, then add water, stir, filter. Repeat the ammonium chloride/water wash until there's no more green/blue liquid, then wash with only water 2-4 more times (it's worth the time to get pure gold). You now have pure gold mud. Smelt gold by adding equal amount flux: 50% ammonium chloride / 25% borax [affil links] / 25% Sodium Nitrate [affil links]. Cover gold/flux mix with borax and you're ready to smelt your gold into bars, nuggets, or whatever. You got pure gold. Have fun and also please read up on aqua regia and be safe: the fumes/gas coming off can melt off/ burn skin, eyes, hair, lungs. Be safe; you can die doing this if you're stupid and refuse to be safe.
Josh Andrews- Juneau, Alaska
March 14, 2012
Q. My problem is that some of the gold jewelry I have is not marked, but it is definitely gold. I was told that I would be able to extract the gold if I left the jewelry soak in HNO3 (strong pure nitric acid for several days). After several days, all that would be left is the gold. Is it actually that easy or is there more to it?
Joel EricksonCustomer - Illinois
September 20, 2008
Q. In recovering gold fines from the heavies and black sands from panning my research on mercury method mentions "charged mercury" as more effective in the attaching to small gold particles than regular mercury.
Would like to know if the difference is worth "charging" my mercury or using it in the natural state. I have found directions to "charge" the mercury but it mentions that the mercury will be solid when fully charged. How is the charged mercury used in a solid form?
- Springfield, Oregon
September 22, 2013
A. Too many chemicals can ruin the quality of gold -- and one's life if they are not educated (in reference to safety and precautions during experiments).
Mercury is one of the most deadly, substances in our world without complete protection and knowledge of its devastating effects. One simple mistake can cost a life or bring a shorter life with mental disabilities. Not safe unless process is done under water with professional tools.
Water and Wind motion:
A gold pan a couple cups of water then slowly in a circular motion like a churning wind it can be separated.
Use a magnet to pull out the steel as you would to separate the iron ore from the gold, (smile).
- California usa
February 9, 2014
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