Non-Chemical purple/red solution & gold residue

[WIZZARD]

The Turkevich Method was brought up a few days ago.

My purple solution when ignited looks like gold. I need to know about purple solutions, colloidal gold and the best way to bring suspected colloidal Au to a size metal that can be filtered. Cementation on stainless steel looks good, but not efficient for large amounts, I'd rather drop larger metallic gold chunks, filter it, rinse it, and met it. Has any one dropped metallic gold from a purple/red solution of suspected gold? Nanoparticles are hard to filter. If I boil it more it turns red, however is it better to go for the gold while purple or red. Is the purple/red color due to the size of the wave length of light when combined with tiny tiny nanoparticles of Au?




The picture to the left is the purple solution. The one on the right purple solution residue left on stainless steel surface after slow ignition, cementation and cherry red heat from a torch.

There may be a few ways to bring down Au in larger particles than nanoparticles, Someone got suggestions. Electro cell? Maybe? No mercury or cyanide or Soxhlet extractor, please.

WIZZARD

 

[qst42know]

Have you considered copper for cementing? Copper will drop any PMs without including other base metals.

 

[machiavelli976]

Hi Wizzard ! what is your goal using Turkevich method? too much sodium citrate won't drop any gold. it will remain in suspension for ever. better boil to syrup your solution, dissolve with AR again and drop with an anorganic compound.

 

[Barren Realms 007]

The Turkevich Method was brought up a few days ago.

My purple solution when ignited looks like gold. I need to know about purple solutions, colloidal gold and the best way to bring suspected colloidal Au to a size metal that can be filtered. Cementation on stainless steel looks good, but not efficient for large amounts, I'd rather drop larger metallic gold chunks, filter it, rinse it, and met it. Has any one dropped metallic gold from a purple/red solution of suspected gold? Nanoparticles are hard to filter. If I boil it more it turns red, however is it better to go for the gold while purple or red. Is the purple/red color due to the size of the wave length of light when combined with tiny tiny nanoparticles of Au?




The picture to the left is the purple solution. The one on the right purple solution residue left on stainless steel surface after slow ignition, cementation and cherry red heat from a torch.

There may be a few ways to bring down Au in larger particles than nanoparticles, Someone got suggestions. Electro cell? Maybe? No mercury or cyanide or Soxhlet extractor, please.

WIZZARD

You would be better off and loose less values if you let it settle and then siphon off the liquid when your gold setles to the bottom of your container.

 

[lazersteve]

Wiz,

Try boiling with muriatic acid.

I've also read that colloidal suspensions may also be precipitated by saturating the solution with salt.

Let us know what you find.

Steve

 

[WIZZARD]

Thanks for the response.

I like the copper idea, but as I understand it the Au/PGM's are not in solution, but in Colloidal gold, also known as "nanogold", is a suspension.

A set of copper electrodes might cause an copper ion to push out Au?

It won't settle. I made some carbonize nano particles three years ago using citric acid in a solution using carbon electrodes spaced 1/8 inch apart. The solution sat for three months and a very fine powder with gold on one side and PGM shinny looking metal on the other settled out. I could not find a filter to filter it. I vacuumed off the top clear solution and added water and got what looked like micro glitter, still would not filter and stayed in suspension for very long time. If I place a laser beam through the solution the beams shows very fine glitter. I was told I did a electrocoagulation number on the solution and metal took sides as a results.

Boil it down to syrup is a good way and should work, I was hoping to find a way to avoid the boil down.

I've been doing some mad science and this purple solution came up last week and a post about purple came up a few days ago, which I thought I found another way, how ever reading about making making this from AuCl sodium citrate seams like there might be a way to reverse the Au back out selectivity?

WIZZARD

 

[WIZZARD]

Steve

I saw your post after my last post. Salt.HCL worth doing. Maybe I'm looking for a Utopian solution, see ya in Utopia. Most likely I'll try them all.

WIZZARD

 

[Oz]

I have heard the same thing as to using salt but I would only try a small sample. If it does not work it would be a PITA to work other options around the salt.

If you are convinced it is elemental I would also try a small sample boiling it down (not dry), then add HCl then Cl2 gas or nitric then precipitate. Your solution color change to yellow would be your indicator as to level of success.

 

[shyknee]

i still have a purple solution.that i think was just some tin that made it by my predigestion ,before doing the AR.
Well there was no purple until i diluted and denoxed with UREA.then even thou it was purple i still added SMB and had a descent drop the purple stayed so i saved it.
i dont think their is enough to go after (into the stockpot it should go right ?)I will try the salt on a sample see what happens
thanks guys

 

[WIZZARD]

Thank you all for your suggestions.

This purple solution was just happen stance and the posting this week about purple solutions was good fortune.

When one finds a mystery without answers it is much harder to figure it out on your own. The forum seams to be working, thanks.

I should explain how this came about and it might help solve the problem of what to do with a serendipitous purple solution, when tin was not not added.

I have acquired some old amber Ion Exchange resin. The owner got it from surplus metal dealer. Who knows what's in the resin it sat around for years in stainless steel tanks? Last year I suspected the amber resin had gold and other elements. I saw gold sometimes and other times nothing, maybe hot spots. I put it on the back shelf. I've been working with modern new resin and learned to elude values, however still complex. The new resin will not produce the purple gang. That another subject!

I added the amber resin, (suspected of having NM, but shows a very weak residue when ignited) to some of my complex ore solutions and tested this with my eluding solution and got the purple solution. The new resin is totally different and expensive, my though was reuse the old in my new solutions and see what I get.

Elude with oxalic/thiourea, got a very gray solution with solid moss like matter, filtered, added powdered zinc and got a heavy brown/gray froth, added HCL to drive the zinc, and it turned purple and very white cream precipitant. Let set for 24 hours and filtered the white cream (I'm thinking the white cream is Ti), however the purple solution is remaining. When reduced to syrup and ignited............gold.

By serendipity I got what I think is stable nano colloidal gold purple solution.

My point is three fold; One, how to best reduce the nano colloidal to larger metallic gold without boil down. Two, can zinc in complex solutions cause a drop of nano colloidal NM's and be missed all together?, Three, how to apply it as a process when confronted with complex materials.

The zinc did what it is cracked up to do, but in micron size, anyone using zinc and not getting the drop, expected, might be missing the values in colloidal conditions?

Serendipity=Being the right place, at the right time and thus benefiting from it,....err......maybe.


WIZZARD

 

[Palladium]

http://www.scribd.com/doc/6660515/Zeta-Potential

 

[qst42know]

If this solution cemented to stainless, how is it a suspension?

 

[Palladium]

If this solution cemented to stainless, how is it a suspension?

Van der Waals forces include attractions between atoms, molecules, and surfaces. They differ from covalent and ionic bonding in that they are caused by correlations in the fluctuating polarizations of nearby particles (a consequence of quantum dynamics).

http://en.wikipedia.org/wiki/DLVO_theory

 

[qst42know]

Ok, I see that it can happen, though much of that link went right over my head.

Would this reaction be called cementing then?

 

[WIZZARD]

If this solution cemented to stainless, how is it a suspension?

The oxygen and hydrogen of water have a dipole sharing of their electrons, thing going on. When in contact with the nano metal in suspended and the surface of the spoon some kind of electron interaction takes place. You can tell I'm not a nuclear physicist, but when I use the term around one, he didn't correct me on it. Pt and other metals when very small will fuse, not a full melt but close. Pt for example, when in micron sizes can melt at temperatures way below the normal melting point of Pt even cherry red from a propane touch. Not to a pool, but fuse together on the surface of a spoon.

If I have a solution with metal in it and evaporated the H2O I have a residue. If the solution is made up of other elements that will flash off or go to vapor and leave a metal residue, I can see that what looked like a clear solution can be full of metal elements.

I use a laser beam from a pointer and shin it through a solution in dark box and I can sometimes see micro glitter, that might be a suspension. If it is a solution it can be clear, with no color, do not assume it is free of metal. I use the spoon test just see if solutions have interesting residues. You can learn a lot from the smoke, the color changes of the solution and then the residue.

A shinny silvery metal may or may not be Pt, however I'm sure it's not organic. I use 4 for dollar stainless spoons, a scientist friend told me they call them spatulas and cost more that few bucks a shot. I don't mind spending 25 cents on A clean spoon and I know if I neutralized the solution I get very little transfer of spoon alloy. I do not use sodium in the solution, its messy and at the end the sodium melts and combines with the residue, and I have to boil it in water, to dissolve the salt and then the residue is still messy. If the solution is acid, I know some cementing is going first, I can see it. Stop the flame rinse and keep going and see some very interesting residues. Scrap the residue from the spoon to test tube or beaker and use different acids, bases, or what ever, to see what goes or what is reaming. When I had a Vreeland spectrometer I would place the scrapping in the test unit to see what I've got. Sure would like one now.



I'm very confident the metal on this spoon is not an orange peel.

Sorry for the song and dance, but I detected that some details were in order to explain how I get my metal pictures so clean of junk.
Use a hood as these vapors can become interesting residues on you or in you.

WIZZARD

 

[lazersteve]

Doug,

Transfer a few flakes of that residue and a four drops of HCl along with a prill of sodium nitrate into a small test tube or watch glass.

The metal should not react at this point.

Next, apply some heat to put the metal into solution.

Heat a little more to drive out the NOx and add four more drops of HCl.

Finally add a drop of fresh stannous chloride.

Any platinum present will give you an orange-red color.

This is a very fundamental test and can be performed in a matter of minutes, after that no more guessing as to whether or not Pt is present, only question is how much.

Steve

 

[WIZZARD]

Steve

Thank you, I will.

I have some questions about possible interfering reactions:

The starting material has a wide range of metals. I have two kinds of Ion Exchange resin, and AC used to weed out the gauge. I can elude the collecting media, with a number of methods, and end up with a number of interesting residues. Some residues are in powder form, and some have a wide range of metallic's.

The direction I'm taking is; The metal will most likely have more than one metal as this stuff gives, "refractory", its definition. With that said, will the chemical test colors you out lined, be effected by other NM's and or rare earth's present ? Example; Au,10% Pt 20%, Pd 10%, Rh 20%, Ir15%, Ru 5%, 20% unknown.





The spoon used was a large SS serving spoon, thus starting volume was greater than a tea spoon, and it came from a reduced solution. No microscope needed with this one.

Remember the starting material was made soluble by salt compound and all the PGM's, have been made some what soluble in weak acids. Most of my solutions are yellow, and some are deep amber, and others maroon.

This leads back to the purple solution, I made more and boiled in salt, no drop, added SMB no drop, however the ignited residue is very golden. The color this time is deeper purple. Added AR and it's still purple. So maybe the purple is a metallic nano alloy of Au/PGM? I'm thinking AuRh.....with just enough Rh/PGM to keep it insoluble?.............just thinking out loud........!!!?????..Oops....Blew a fuse!



Can the test you out line be used on the purple direct?

I know this has a few elements to it, but they are interlinked to the over all problem.

WIZZARD

 

[lazersteve]

Doug,

The salt suggestion was to saturate the test sample with sodium chloride, not to boil it in a saline solution. The salt acts to occupy the solvent molecules thereby forcing the suspected colloid out of the solution. You should try saturating a small sample with salt and see what happens.

Another possibility for your purple solution is dissolved nickel, test for nickle by adding ammonia water to a sample until basic, then a drop of DMG will give the tell tale voluminous pink precipitate if nickel is present.

Testing for mixed PMs involves elimination of the interfereing metals via sequential use of reagents or use of selective extraction solvents.

Here's one example:

1. The residue in the spoon is dissolved in hot AR and denoxxed as typical.
2. Filter the solids from the solution.
3. Au is removed via Ferrous sulfate as a dark powder.
4. Pd is removed via DMG as a voluminous yellow salt.
5. Pt is indicated with room temperature stannous chloride: positive = orange-red.
6. Any Rh which dissolved in the AR is indicated with heating with stannous chloride until solution turns yellow the solution then goes rose colored after cooling.

The residue from the above reaction may contain Ir, Os, Ru, or Rh plus other junk.

No offense, but you seem to avoid the tried and true methods of proving your residues are of value. There is no need to reinvent the discoveries of the chemists of ancient times, all of the elements in the periodic table already have specific techniques to extract and test for if present. It's just a matter of learning these techniques and having the reagents on hand. I'll be very glad to help where I can if you would like to learn.

Steve

 

[Harold_V]

Any chance there is tungsten in that solution? That sure would account for the strange color.

I often wonder why folks don't follow prescribed methods. I guess it all depends on one's objective.

I was satisfied to follow well known and accepted practice in my refining venture. I spent my time accumulating value instead of attempting to redefine the wheel, which I found to be sufficiently round at the outset. YMMV!

Harold

 

[WIZZARD]

Steve I'll take you up on the offer....That's why I joined the forum.

Sure would like to do a mind melt, that would save a lot of time.

Any chance there is tungsten in that solution? That sure would account for the strange color.

Your guess is as good as any to what was in the start up resin, before I soaked some in my solutions. The tanks were 500 gallon solution treatment tanks and full of the amber resin, a base line test shows some gold. A refinery told me there are NM's in the resin but are not compatible with their system and I don't have 10 tons of it, and I'm not a company. They burned some, and the residue had some gold in it. I got a little perturbed...........when I learned they could not account for the vapor.

I'm working on some of those normal procedures as the forum is very helpful. Used HCL/clorox on some row material, filtered, used Sodium Metabisulfite, and got a tan drop today, still need to deal with the tan drop. That's a commercial coffee filter, 12 inches across. Got suggestions?



Placed some in a spoon and added a flame and got this brown residue. Look's like it could be the right stuff?


I plan to work with the tan drop by drying it and fluxing it, and place in the oven with a graphite crucible and maybe get a button?

WIZZARD