Non-Chemical Good gold refining method?

[Alaska5]

I am still learning and I need opinions.

I want to put beach sand into HCL & Bleach to dissolve the gold. Then use SMB to precipitate into gold powder.


Is this a valid concept...will free/natural gold be able to be dissolved directly then dropped?

Also would I have to worry about other metals being dissolved and interfering with the SMB drop? Will they be present in my final gold powder?

I've also thought about doing this with crushed bedrock.

Any help would be appreciated!

 

[nickvc]

Welcome to the forum.
The simple answer to your question is it’s not a good plan, not only will you dissolve gold but most other metals, you may well emit poisonous fumes plus the toxic fumes from the material, you will also end up with a toxic solution to properly dispose of.
Generally the major players use cyanide to leech the material which on its own has massive dangers if not handled properly.
You may well be better off trying to concentrate the values first and then decide what method to research to refine your material.

 

[Thipdar]

I am still learning and I want to get opinions on a concept that I've been developing.
I have access to quality black sands/ bed rock and my idea is to put the sands/ bedrock into a rock crusher. Then I will put the resulting powder into aqua regias. Then I will strain the solution, then drop with SMB.

Is this a valid concept...will free/natural gold be able to be dissolved directly then dropped?

What AR will be able to dissolve free gold in black -sand powder?

Also would I have to worry about other metals being dissolved and interfering with the SMB drop? Will they be present in my final gold powder?

Note: I've also thought about using certain gold containing beach sands instead of crushing bed rock.
Any help would be appreciated!

If you want to concentrate your black sands, run them (in small batches) through a centrifuge. The heavies will go to the bottom of your centrifuge tubes. Decant and discard the lighter junk (unless you've got a better use for it). It may take a while, but it's much better than trying to deal with all of the junk that's also present in the sands.

-- Thipdar

 

[Alaska5]

Welcome to the forum.
The simple answer to your question is it’s not a good plan, not only will you dissolve gold but most other metals, you may well emit poisonous fumes plus the toxic fumes from the material, you will also end up with a toxic solution to properly dispose of.
Generally the major players use cyanide to leech the material which on its own has massive dangers if not handled properly.
You may well be better off trying to concentrate the values first and then decide what method to research to refine your material.

I don't want to concentrate them, I want to dissolve the gold out of the rock powder with a chemical solution, then pour the solution into a bucket and precipitate the gold out of the solution. The end goal is be left with gold powder.
Would HCL and bleach work for the solvent, and SMB work for the percipitant?

 

[butcher]

Aqua regia or its substitutes are a refining process, it is not a recovery process, you will not be successful trying to use it for a leach of black sands, the iron will dissolve or displace any gold, with ore deadly gases are produced.

Gravity methods are easy and are your best bet for recovery of the free gold.

 

[galenrog]

NEVER expose any substance to acids (or bases) unless you are certain of the result and follow appropriate safety protocols. Your life is in the balance. If you are unlucky, you may simply destroy 70+% of your lung function. If you are lucky, you may simply make a gosh awful toxic mess.

Fine gold is easy to liberate from beach sands by gravity methods. I know several people who do well doing so. Check out gpex.ca. They can help you out a lot.

Time for more coffee.

 

[Thipdar]

Welcome to the forum.
The simple answer to your question is it’s not a good plan, not only will you dissolve gold but most other metals, you may well emit poisonous fumes plus the toxic fumes from the material, you will also end up with a toxic solution to properly dispose of.
Generally the major players use cyanide to leech the material which on its own has massive dangers if not handled properly.
You may well be better off trying to concentrate the values first and then decide what method to research to refine your material.

I don't want to concentrate them, I want to dissolve the gold out of the rock powder with a chemical solution, then pour the solution into a bucket and precipitate the gold out of the solution. The end goal is be left with gold powder.
Would HCL and bleach work for the solvent, and SMB work for the percipitant?

If you don't concentrate them, you'll probably end up dealing with an iron refining process rather than a gold refining process. Don't put the cart before the horse! You may eventually get some gold out of the deal, but in the meantime, you'll have wasted time, energy, supplies and possibly other resources.

Do a quick and easy check: test some of your black powder with a magnet. Make sure the powder is dry first. If there's a significant part of the black sands that are magnetic, remove them (either magnetically or with a centrifuge) before you start using any chemicals.

There's a reason we follow the "Reactivity Series"!

-- Thipdar

 

[nickvc]

Welcome to the forum.
The simple answer to your question is it’s not a good plan, not only will you dissolve gold but most other metals, you may well emit poisonous fumes plus the toxic fumes from the material, you will also end up with a toxic solution to properly dispose of.
Generally the major players use cyanide to leech the material which on its own has massive dangers if not handled properly.
You may well be better off trying to concentrate the values first and then decide what method to research to refine your material.

I don't want to concentrate them, I want to dissolve the gold out of the rock powder with a chemical solution, then pour the solution into a bucket and precipitate the gold out of the solution. The end goal is be left with gold powder.


Would HCL and bleach work for the solvent, and SMB work for the percipitant?

In which case you are going to have to look to a cyanide based leach, if used fairly weak it is very selective but you then need large volumes to extract decent amounts of values, or you look to extract the metals via a cell, that allows the solution to be re used.

If you search for Deano he has many very helpful ideas and processes that may give you a start, I’m afraid what you want and what is possible are two very different things as chemistry has set rules, if it was that easy do you not think someone would already be doing what you are suggesting, if you still want to use acid based leeches then you need to concentrate your values and have assays done to make sure you, neighbours and the environment are safe before adding any chemicals to your material.

 

[Deano]

When researching a proposed recovery method for gold the first thing to do is to see what the mining industry does for similar situations. They have had decades of experience in working out the best and safest methods.

When dealing with milled hard rock the industry standard method is cyanide leaching followed by carbon adsorption of the gold cyanide complexes.

This method is always run alkaline for safety reasons, this alkaline condition also means that dissolution of base metals is minimised.

Hard rock deposits will always have iron and other base metals such as copper present, if you use an acid system you will dissolve up these base metals.

This is apart from the milled rock itself possibly reacting with the acids being used and the need for all wetted plant parts to be acid proof.

Acid leaches will always present you with a leach solution full of base metals these base metals will be present in ratios hundreds or many thousands of times the level of any gold. You will have changed the problem from separating the gold from the rock to separating the gold from the dissolved base metals.

Acid digests are used in the mining industry only for assay purposes, definitely not for production scale.

Deano

 

[Geo]

galenrog is absolutely correct. It could be contaminated with mercury or cyanide. Gold is a lure and where ever you are digging, it's a good bet that someone has already been there and done that. You have no idea what they were using. It's best to have a sample tested and assayed. The cost can save you a lot of time and money down the road. If you think you have hit the pay dirt, it would be chump change any way. At least you will know what you are working with and that will tell you what you need to know to refine it.