Need help dissolving tungsten oxide

[Anonymous]

I am hoping lou will chime in here,but I want anyone with experience to give me some advice.
I have ran about 40 pounds in the new ball mill.I processed about half with no success.Before I built the new mill I never had a problem processing cpu powder,but I have run into several problems.First of all,after trying to process about half of the powder(with no success),I discovered that I had iron in my powder.So I removed the iron(chemically) from the powder already processed,and removed it(via magnet) from the unprocessed powder.Then trying to process all of it in 2 five gallon buckets,I realized I have large amounts of tungsten from the lids on the chips,and now I guess it's turned into tungsten oxide(fine white powder).The problem is getting the gold into solution and then seperating it from the oxide.I have more details,but this pretty much sums it up.Any ideas?

 

[Barren Realms 007]

What about breaking the ceramic's away from the heat sinks and run a load, or run a load that has no heat sinks on them?

Have you tried some peroxide?

 

[Lino1406]

Tungsten oxide will dissolve in hot KOH, giving tungstate solution

 

[Anonymous]

Tungsten oxide will dissolve in hot KOH, giving tungstate solution

Thank you Lino,however since I started this thread,the gold has leached into the AR.I just needed to let it sit for about a week.Now I have a rediculous amount of nitrates to expell.

 

[Lou]

Mic, I hadn't read this thread but it confirms my suspicions.

Just let it all leach, dilute, filter, and cement. Take the recovered material, boil in base, decant/rinse 3X, then aqua regia or whatever method and evaporate and go for the pure gold.

Lou

 

[Anonymous]

I guess I should have updated this........
the gold appeared to be leaching into the AR,however it ceased and reattached to the tungsten.
I tried boiling some of the tungsten powder in sodium hydroxide earlier today but I am not familiar with testing for PM's in a base.I am so dam frusterated over all of this crap!I've processed for a long time and I have never had such a hard time with a material.And what REALLY irritates me is the fact that I could've removed all of the tungsten plates had I known this was going to happen.

 

[Barren Realms 007]

For those that go before us with thier test's we dearly thank you. Life is full of learning experiences that will stay with us forever. You get an AAA+++++ for your determination and persistance to see this thru to the end. Although we can not be there personaly to help and support we are with you in spirit. My man/my hero. 8)

 

[Anonymous]

Thats so cool of you to say that.
Harold and lou suggested I try some thio* or cyanide.I am currently talking to a friend about getting some cyanide from him.
I have my fingers crossed,prayers prayed,a big cup of coffee and a lot of determination.

 

[Harold_V]

If, by chance, you do manage to try cyanide, be damned sure you keep the pH above 9½. Don't smoke, and don't lick your fingers! :lol:
Above all, do not introduce cyanide to the material so long as it's acidic.

It's been way too many years for me to remember the titration process, to determine free cyanide, but know that it takes very little to dissolve gold---and that it becomes selective when used in a very weak concentration. Little would be consumed, assuming you have no cyanicides present.

I may be wrong, but the very fact that you kept experiencing precipitation of gold on tungsten indicates to me that it was on the decline. Given enough repetitions of what you were doing, you'd eventually run out of elemental tungsten.

I really liked the suggestion to wash with sodium hydroxide, I believe it was. It that dissolves the tungsten, you'd be well on your way to recovering the locked up values without risking the use of cyanide. In the hands of one with no experience, it can be potentially dangerous. Insure that animals can't access your solutions if you proceed.

Harold

 

[Harold_V]

I tried boiling some of the tungsten powder in sodium hydroxide earlier today but I am not familiar with testing for PM's in a base.I am so dam frusterated over all of this crap!I've processed for a long time and I have never had such a hard time with a material.And what REALLY irritates me is the fact that I could've removed all of the tungsten plates had I known this was going to happen.

It isn't necessary to test for gold in sodium hydroxide in that it won't stay in solution. Your objective would be to eliminate tungsten, nothing more. If you find that it dissolves, process by that method until it has all been dissolved, or converted to what ever it creates. The compound is highly unlikely to be able to precipitate gold. At that point, you should be able to dissolve the gold and keep it in solution, as there will no longer be the necessary electron present that permits precipitation. The biggest problem you'd face, then, is rinsing the values from the resulting mud.

Harold

 

[Anonymous]

Thanks for your concerns harold.All of the processes would be done in a closed building with very adequate ventilation,and more than proper safety gear.I am aware of complexities and dangers of Cn,and the importance of ph balance.You've known me longer than almost anyone on this forum,and you know I will be safe.......you know what I have to live for,and protect.
I have a member working with me to try to extract it using a different leach method.I will email you and give you the details after he writes back this next time(along with the progress,as promised).