Advice needed.

[BMarsh555]

First time posting and hoping just to get pointed in the right direction. I have 2 55g drums of catalyst bought at an estate sale. Neither drum has been opened from factory and in new condition. I tracked down a msds number and found it is 90% aluminum oxide, 5% tin dioxide, 1-2% platinum and the other 3-4% wasn’t disclosed. For the past 6 months I’ve tried numerous ways to try and leach with aqua regia solution and have had success but with minimal yield. I started with trying to leach with the catalyst in ball form and could never get the solution completely out of the cracks in the balls. No matter how many washes, the standouts chloride test still showed extremely strong positive ever after I got the balls from a strong yellow color to sheet white.
From there I tried grinding up the catalyst in a coffee grinder and it worked great. Now my biggest problem was it was extremely hard to filter even with a vaccum. Even after the filter was complete days later, I still couldn’t get the solution to come completely out of the ground catalyst.

I move on to trying to melt it down with an arc furnace. Seeing that the catalyst isn't metallic, I could melt it in a usual arc furnace fashion. Taking two carbon gouging rods and melting it down in a homemade crucible I’ve made out of ramtech plastic ramable refractory. It holds up great. When melting it down I can see the platinum forming beads and dancing around in the puddle. Now the problem is that I can’t get all the beads to come together and collect, I’ve tried lead as a collector metal and it still doesn’t seem to be working. I’m looking for advice on the next step I should take. I would prefer melting then processing with aqua regia to obtain a purer platinum, but I am open to all suggestions. I have read all material that is suggested and hope I’ve gave enough clarity on the situation.

 

[Yggdrasil]

First time posting and hoping just to get pointed in the right direction. I have 2 55g drums of catalyst bought at an estate sale. Neither drum has been opened from factory and in new condition. I tracked down a msds number and found it is 90% aluminum oxide, 5% tin dioxide, 1-2% platinum and the other 3-4% wasn’t disclosed. For the past 6 months I’ve tried numerous ways to try and leach with aqua regia solution and have had success but with minimal yield. I started with trying to leach with the catalyst in ball form and could never get the solution completely out of the cracks in the balls. No matter how many washes, the standouts chloride test still showed extremely strong positive ever after I got the balls from a strong yellow color to sheet white.
From there I tried grinding up the catalyst in a coffee grinder and it worked great. Now my biggest problem was it was extremely hard to filter even with a vaccum. Even after the filter was complete days later, I still couldn’t get the solution to come completely out of the ground catalyst.

I move on to trying to melt it down with an arc furnace. Seeing that the catalyst isn't metallic, I could melt it in a usual arc furnace fashion. Taking two carbon gouging rods and melting it down in a homemade crucible I’ve made out of ramtech plastic ramable refractory. It holds up great. When melting it down I can see the platinum forming beads and dancing around in the puddle. Now the problem is that I can’t get all the beads to come together and collect, I’ve tried lead as a collector metal and it still doesn’t seem to be working. I’m looking for advice on the next step I should take. I would prefer melting then processing with aqua regia to obtain a purer platinum, but I am open to all suggestions. I have read all material that is suggested and hope I’ve gave enough clarity on the situation.

Welcome.
How well versed are you in refining?
The salts of PGMs are exceedingly toxic, but not acutely so.
We have members dying from these so I hope you have a proper lab set up.
2-3 grams in total for the whole catalyst.
If you just take a little bit for testing it will hardly be visible if you cement it out.

Smelting is what the big boys do but they use fine Copper strands or powder as collector metal.

 

[BMarsh555]

Welcome.
How well versed are you in refining?
The salts of PGMs are exceedingly toxic, but not acutely so.
We have members dying from these so I hope you have a proper lab set up.
2-3 grams in total for the whole catalyst.
If you just take a little bit for testing it will hardly be visible if you cement it out.

Smelting is what the big boys do but they use fine Copper strands or powder as collector metal.

I do have all proper set ups. I use a ventilation box for fumes and use full face mask with ovga filters and elbow high chemical gloves. I’ve turned all salts into platinum sponge after drying. I read all the books that are advised to read and did months of research before starting this. Each drum has a net weight of 285 pounds. I would figure there are more than 2-3 grams in total. 1% of 285 is 2.85 pounds. I have copper powder, would that be suggested to use over lead?

 

[eaglekeeper]

I still couldn’t get the solution to come completely out of the ground catalyst.

Unless you're going to use pyrometallurgy, there's no reason to grind it up. All the PM's will be on the outside surfaces.

 

[Yggdrasil]

I do have all proper set ups. I use a ventilation box for fumes and use full face mask with ovga filters and elbow high chemical gloves. I’ve turned all salts into platinum sponge after drying. I read all the books that are advised to read and did months of research before starting this. Each drum has a net weight of 285 pounds. I would figure there are more than 2-3 grams in total. 1% of 285 is 2.85 pounds. I have copper powder, would that be suggested to use over lead?

Sorry I read that wrong, I read 285g.

Yes I believe Copper is a better collector than Lead.
But you also need the correct flux mix probably also some thinning agents as well.
I think I saw it was recommended to use Boron based flux over Sodium based.

 

[BMarsh555]

Sorry I read that wrong, I read 285g.

Yes I believe Copper is a better collector than Lead.
But you also need the correct flux mix probably also some thinning agents as well.
I think I saw it was recommended to use Boron based flux over Sodium based.

I have used borax in a few different test runs, and borax mixed with soda ash. It’s just crazy to me that I can see so much of it in the puddle and it not collect. It all sits on top as if the aluminum oxide had a higher specific gravity in liquid form.

 

[Yggdrasil]

Do the Aluminum Oxide melt properly?
Do you use Cryolite or Fluorspar?

I have used borax in a few different test runs, and borax mixed with soda ash. It’s just crazy to me that I can see so much of it in the puddle and it not collect. It all sits on top as if the aluminum oxide had a higher specific gravity in liquid form.

 

[4metals]

If you get the metal to pool you are not losing it, or losing all of it, to volatilization as a salt. Add cryolite to the melt to thin the alumina and hopefully get the Platinum to pool in a fluid slag. Alumina is used as an abrasive because of it’s deep fissures and hardness, to collect all of the metal you need to melt the alumina. Cryolite makes for a long slow melt as in hours to make the slag fluid.

 

[Yggdrasil]

I have used borax in a few different test runs, and borax mixed with soda ash. It’s just crazy to me that I can see so much of it in the puddle and it not collect. It all sits on top as if the aluminum oxide had a higher specific gravity in liquid form.

Both Borax and Soda Ash is Sodium based and if I understand it correctly is very thick.
You will need Cryolite or similar with these.

 

[BMarsh555]

Do the Aluminum Oxide melt properly?
Do you use Cryolite or Fluorspar?

I have used neither but cryolite is the next step I believe. It will dropped the melting point of the aluminum oxide but not the platinum.

 

[BMarsh555]

If you get the metal to pool you are not losing it, or losing all of it, to volatilization as a salt. Add cryolite to the melt to thin the alumina and hopefully get the Platinum to pool in a fluid slag. Alumina is used as an abrasive because of it’s deep fissures and hardness, to collect all of the metal you need to melt the alumina. Cryolite makes for a long slow melt as in hours to make the slag fluid.

Thanks for the information, I will order the cryolite today!

 

[4metals]

I will order the cryolite today!

Go easy with it and add it slowly to the pool of flux, it is hard on crucibles too so be wary of crucible erosion when you pour, check before you re-use a crucible.

 

[Dreamer]

Don't use the typical clay crucible, the cryolite will eat through it. My experience anyways.