# Smelting incinerated ICs



## kjavanb123 (Dec 7, 2014)

All,

In a new smelting project I mixed equal volume of screened pulverized IC ashes with borax, and smelted it with 60g of copper wires, then poured the molten mix into my V shaped steel mold, let it cool, broke the big chunk with hammer and found a solid piece of alloyed metal which is due for a fire assay Au, PGM, and ICP other elements.

Here are few photos for your viewing,

- Molten mix after it was cooled to room temprature,



- Slag broken to reveal this alloy,



Regards,
Kevin


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## nickvc (Dec 7, 2014)

Kevin please take this as its meant but I suspect your leaving values in your flux, keep and re run at a later date and thin the flux so all metals have a chance to amalgamate, a good long heating with plenty of agitation should drop most of any trapped values, a cone mould or similar will help failing that simply crush and screen and melt any resulting prills of metals.
I'm pleased to see you trying different methods and wish you luck.


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## kjavanb123 (Dec 7, 2014)

Nick,

Thanks for your comments. Melting was done inside an induction furnace which I believe produces that agitation effects through induction. By visual inspection there are only few prills of metals. To be sure I will remelt the slags one more time using more borax and leave it in furnace for longer at least half an hour. Pour it to V shaped mold which is similar to cone mold but in straight line.

Best regards
Kevin


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## Platdigger (Dec 7, 2014)

Kevin, try giving it at least an hour and see how that does.
And like Nick said make sure the slag is thin enough.


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## kurtak (Dec 8, 2014)

Kevin 

Soda ash in your flux will help make it run thinner (more fluid) its harder on crucibles but the more fluid the molten flux the better the circulation the better the metal settles out of the slag which results in less ball metal hung up in the slag also a little fluorspar will help make the flux more fluid

Kurt


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## kjavanb123 (Dec 8, 2014)

Kurt,

Thanks for the tip in using soda ash. That is something I did not use for flux used in this project. Induction furnace does a good job agitating the molten metals. I will have to let it stay longer in the furnace.

Best regards
Kevin


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## Harold_V (Dec 9, 2014)

I agree that thinning is a good idea. The slag should be colored, but not cloudy, as it appears now. The greater volume of flux will aid in that problem. It is my opinion that it should resemble obsidian. A small amount of fluorspar added to the flux formula will liquefy such that it may pour like water. 

Even without induction heating, I was able to extract values from my waste materials to the point that the resulting slag was too low in values to be reprocessed with litharge (determined by fire assay). I used a small amount of fluorspar. It is much like soda ash in that it encourages rapid dissolution of the crucible. 

Harold


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## kjavanb123 (Dec 9, 2014)

Harold,

Thanks for the comment. Please kindly advise what do you think about the golden color of the metallic alloy? Could that be Cu-Au alloy since the materials were incinerated IC ashes.

I am making another flux, this time incude 4 parts volume soda ash along with 4 part borax, and keep it a lot longer in the induction furnace to see what happens. 

Last time I poured the slag seemed fluid. I am thinking to use lithrage next time see if I can collect the precious metals, dissolve in nitiric determine how much gold or silver I can recover.

Best regards,
Kevin


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## patnor1011 (Dec 9, 2014)

That is just colour of brass Kevin. 
While IC do contain gold, amount is not that big to represent in this colour. You can see it with sellers of melted pins on ebay, they use this colour to capitalize on greed of uneducated people. You will see the same colour if you try to melt batch of IC which do not have gold bonding wire.


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## Harold_V (Dec 9, 2014)

kjavanb123 said:


> Harold,
> 
> Thanks for the comment. Please kindly advise what do you think about the golden color of the metallic alloy? Could that be Cu-Au alloy since the materials were incinerated IC ashes.


I think I'd agree with patnor. Whether you used copper or not, assuming you managed to get a collection, I expect it would be yellow in color, and most likely would have nothing to do with the presence of gold, as it is in just trace amounts. The color of your recovered metal leans towards a copper color more so than that of gold, which is most likely due to the fact that you have added a large percentage of copper, used as a collector. The color, therefore, likely means very little, if anything. 



> I am making another flux, this time incude 4 parts volume soda ash along with 4 part borax, and keep it a lot longer in the induction furnace to see what happens.


Working out a good ratio is an excellent idea, as is the idea of determining how long it must "cook". 

As I don't know anything about the induction furnace in use, I feel I should make mention. If you are melting directly in the furnace or not, you risk penetrating the refractory, destroying the coil. As you increase the use of flux, in particular, soda ash (which is used to dissolve silicon to make glass), you accelerate the destruction of the melting chamber. Keep a close eye on the furnace, to ensure you don't ruin the coil. 



> Last time I poured the slag seemed fluid.


I'm of the opinion that it was not, in spite of how it may have behaved. The opaque color troubles me, as did the mention of finding prills. If your flux is proper, and you've "cooked" the material long enough, especially if you have provided a collector (copper, in your case), there should be no prills. The simple addition of a small amount of fluorspar will ensure it is thin enough. 



> I am thinking to use lithrage next time see if I can collect the precious metals, dissolve in nitiric determine how much gold or silver I can recover.


That litharge has been used as a collector, I don't dispute, but attempting to process with nitric wouldn't be in your best interest, at least not in my opinion. Any silver that may be present would be somewhat difficult to separate from the lead, which will self precipitate as the solution cools. You'd be far better served by cupelling the lead, but that opens a whole new case of snakes for you, and that may not be necessary. It would be a good way to do your testing, but likely not so good in production. 

If you must use a collector, give some thought to using silver. In my case, I relied on silver chloride as a collector, and I was pleasantly surprised to achieve my goal, albeit at the cost of severe erosion of the lining in my furnace, which I considered a small price to pay for so much value recovered.

Contrary to the opinion expressed by some, silver chloride is reduced to metallic silver when melted in conjunction with soda ash, which you already have in your flux. 

Harold


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## kurtak (Dec 9, 2014)

kjavanb123 said:


> Harold,
> 
> Last time I poured the slag seemed fluid. I am thinking to use lithrage next time see if I can collect the precious metals, dissolve in nitiric determine how much gold or silver I can recover.
> 
> ...



Keven 

Forget using litharge - you are talking lead here & trying to part the gold from the lead with nitric is going to use a huge amount of nitric & is going to be a huge mess with a huge amount of lead toxic waste to then deal with & trying to recover the silver from the lead/silver nitrate (for the "small" amount of silver in ICs) is not going to work well --- you would actually be better served to run litharge collected metal in bone ash cupels so the lead goes off into the cupel 

use silver as your collector metal - it is (in my opinion) the better choice for a collector metal then copper - for one thing it takes almost 4 times more acid (nitric) to dissolve away the same weight copper as silver (1 gallon nitric dissolves about 2 lb copper - or 8 lb silver) so you use much less nitric to recover your gold from silver as a collector compared to copper as a collector

also there is what I call the "sponge effect" with molten metals - some metals (when molten) are better at sucking up (collecting) molten metals when they make contact & silver has a better sponge effect then copper & what that means is that though they will both work as a collector metal it is much more important that when using copper that the flux run very fluid with really good circulation in the crucible to insure that you get really good contact of the metals you are trying to collect coming I contact with the copper

Try this as an experiment - take some silver powder put it in a melting dish & melt it with a torch - when you have a glob of molten silver you will also have little beads of silver stuck to the sides of the melting dish which you can collect by "gently" rotating the melting dish around - watch how quickly & easy the glob of silver "sucks up" the little silver beads

Now do the same thing with some copper powder - you will see that the molten copper glob does not "suck up" the little copper beads as quick &/or as easy - in fact you will see that to collect some of the little beads you actually have to jiggle the melting dish so that the copper glob hits them with force to suck them up

I keep about 4 -6 pounds of silver cement on hand to use as my as my collector metal for these very reasons - in fact it is in part why I have made it a point to establish a couple of clients that provide my with contact points - it provides me with a good source of silver that I can buy for much less then buying sterling so I always have silver for a collector metal

Edit - I see Harold already covered much of this as I was typing

Kurt


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## kjavanb123 (Dec 9, 2014)

Gentelmen,

Thanks so much for your well explained posts. This again makes me feel like part of elite club of experienced refiners who have been mentors to me through all these years here.

Kurt,
I read your large vs small volume cat refining with a lot of interest and really well done. So you have already tried using induction furnace smelting CATs and it turned out not profitable? 

I will try this tommorow with silver metal as collector preferly I purchase silver powder or silver chloride powder, mix it well with my basic flux and fine CATs, and let it melt inside a 4lb clay graphite cruicble which sits inside the furnace 160lb graphite cruicble.

So Harold I am well aware of how damaging this flux is with crucible as It cracked so many 4lb crucible I used. Once smelting CATs become success in this clay graphite ones I can change the existing 160lb one with something resistance to soda ash and cryolite.

Best regards
Kevin


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## Auful (Jan 28, 2016)

kjavanb123 said:


> All,
> 
> In a new smelting project I mixed equal volume of screened pulverized IC ashes with borax, and smelted it with 60g of copper wires, then poured the molten mix into my V shaped steel mold, let it cool, broke the big chunk with hammer and found a solid piece of alloyed metal which is due for a fire assay Au, PGM, and ICP other elements.
> 
> ...


May I ask what the was mass of the pulverized IC ashes in this sample? Thanks. How is the ratio of material-to-be-smelted:copper ratio figured? Thanks.


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