Non-Chemical Smelting in India

[kjavanb123]

Here is the lead dore from smelting ICs, it weighs 158.2 grams.


Made the following cupel with portland cement pressed using another heavy pot,


According to video posted by youtuber OwlTeck who is also a member here by the title 30 second cupel making, I put the lead dore in the cupel, used burner to melt it,


In 20 minutes doing this way there was no shrinking of molten lead, so I put my furnace body on top of the cupel and heat it again, this time only when burner was removed from cupel there was smoke coming out.

Watching OwlTech video, it seems like burner had to be put aside once in a while to oxidiation takes place.

More later.

 

[kjavanb123]

Lead ingot started at 151g, after minutes passed and inside furnace, the lead dore weighed 85g, and after more cupelation it went to 40g.

Here is the photo,


This is what 85g looked like after another cupelation, notice the darker piece on top of gray lead, turned out to be copper.


As you can see, lead plus base metal oxide is formed like this dark matters around the lead bead, which can be broken off easily,


Here is the 40g lead bead inside cupel, close inspection could see molten lead looks like a mirror and tiny dots which I assume are oxide of base metals merging from surface of molten lead and drop to the edges,


Finally bead was so small that I had to let it cool, rebuild the cupel by adding more cement so burner can heat it up.

 

[snoman701]

Hoping you have good ventilation!

I have ran exactly zero cupellations, but I have read up on them and I question whether cupel appears to be hot enough (1800 deg F), or uniformly heated, so it may be freezing up?

If taking the torch away helps, it is likely because it allows the lead bead exposure to oxygen. The lead will then boil off, or be absorbed by the cupel. That flame looks more neutral than oxidizing, even with the sodium flare. Try wrapping your cupel in ceramic fiber so that you can heat uniformly, but still allow fresh oxygen to interact with the surface of the lead.

As an alternative, if that torch allows adjustment of oxygen, increase oxygen flow.

 

[kjavanb123]

There is ventilation in place. I finally got the lead bead to a point that oxidizing and cupelation did not shrink it.

Here is after 3rd cupelation,


Final bead that no longer responded to cupeling,


Final weight in oz,


Ran out of nitric acid in my lab, so this has to wait until tommorow to dissolve in nitric.

 

[kjavanb123]

So far tried to dissolve the PM alloy in nitric acid even with heat there was no reaction.

I rinsed the nitric, heated to remove excess nitric, then treated it with hcl and still no reaction.

Tried AR on it, after some times in water heat and solution turned green in color, once the heat was off it stopped reacting, green solution negative for gold.

This morning, tried to dissolve it in dilute sufluric, it bubbled first but reaction stopped after 2 hours.

I am going to melt these along with carbon source with silver as collector this time, and see what happens.

 

[Owltech]

So far tried to dissolve the PM alloy in nitric acid even with heat there was no reaction.

I rinsed the nitric, heated to remove excess nitric, then treated it with hcl and still no reaction.

Tried AR on it, after some times in water heat and solution turned green in color, once the heat was off it stopped reacting, green solution negative for gold.

This morning, tried to dissolve it in dilute sufluric, it bubbled first but reaction stopped after 2 hours.

I am going to melt these along with carbon source with silver as collector this time, and see what happens.

Too much copper halts the cupellation, to get around it you need to add more lead (10 times the weight of the copper), not at once but in increments (10% of the lead when the button freezes). You don't have to point the burner directly at the button as reducing or neutral flame will keep it from oxidising, All you need is enough heat to keep your button molten, and a draft of hot air to oxidise the lead (some times I use heat-gun, or position the burner in a way that the flame creates a draft over the molten pool)
Good read on the subject:
https://ia801408.us.archive.org/11/items/atextbookfireas00bugbgoog/atextbookfireas00bugbgoog.pdf

 

[ashir]

is there any substitute of lead ? as lead is more toxic because of particals. hard to controle!

 

[kjavanb123]

Ashir

You can substitute copper instead of lead, but you need to oxidize the molten metals to purify copper to be 97% or more copper with PMs, then run it in copper cell.

 

[ashir]

thank kjavanb123. snoman and butcher also recomend this to me in my post, lead fumes'
i want your more guide to treat ashes to get a molten metal, what will be the best mathod to oxidise molten metals to get 97% pure copper,? any guide to prepare solution for copper cell. how to make a copper cell at home? i have alot questions to you about smelting. lead fume scrubber. but first teach me on copper cell recovery!

 

[Geo]

A cupel needs to be made of bone ash and Portland cement.
https://en.wikipedia.org/wiki/Bone_ash

 

[ashir]

so my ball mill is ready

my crucibles arrived. 10 kg graphite crucibles

my air blower is here

going to setup coal furnance in next few days
no i want some guide on crucible tongs and con mold
what should be the measurenmebts of a cone mold( iron) to handle 3 kg of fluxes and pms.
which type of tong should be batter to prepare?
and one more
what if i melt the ic's ash without any lead or bismuth, just with soda ash, borax,
then remelt with adding silver and sodium nitrate
and treat with nitric......?

 

[kurtak]

what if i melt the ic's ash without any lead or bismuth, just with soda ash, borax,

Per the underlined - NO - when smelting you need to have a collector metal - that is what the lead or bismuth do - they act as the collector metal - without the collector metal (when using just soda ash, borax) there won't be enough metal to collect & settle to the bottom of the cone mold when you make the pour of the smelt to the cone mold --- instead what will happen is VERY small beads of metal will form in the flux/slag & when you pour it to the cone mold these VERY small beads will remain suspended through out the slag (when it cools down) instead of settling to the bottom of the cone mold

then remelt with adding silver and sodium nitrate

Yes - silver (or copper) can be used as your collector metal (instead of lead or bismuth) - BUT - you want to use it in the original smelt ALONG with the soda ash & borax - NOT - as a re-melt AFTER the original smelt --- & you DON'T need the sodium nitrate


If you really want to get on the right path to smelting - start by reading ALL of this thread


:arrow: http://goldrefiningforum.com/phpBB3/viewtopic.php?f=85&t=25592#p272232

Here are some pictures I posted awhile back about my smelting set up

:arrow: http://goldrefiningforum.com/phpBB3/viewtopic.php?f=40&t=22581&hilit=tongs&start=30#p242087

Here are some pitures of my tongs used for smelting - they are 2 man tongs

First pic are the lifting tongs for lifting the crucible from the furnace

Second pic is the pouring tongs for pouring the smelt to the cone mold

Kurt

 

[ashir]

thanks kurtak
it was just an experimental thought to melt metals without a collector metal. and i put this question so i can get answer without experiment, and you did that, thanks again
very awsome setup. i want read your both mentioned threads many times so i can get more ideas!
and going to make a coal furnance with air blower, if it not work then seecond idea is to use waste oil burner( its also ready for work) both are cheap here.
i am always against lead on one hand( because of toxic fumes) and at same time like to use the lead on other hand as a suitable collector,
bismuth is just 22 dollars per kg in pakistan, still cannot get litharge so i do not know its price.
tongs ideas are nice in your setup,
i was thinking to use one step picking the crucible and pouring it, but it can be done with small crucibles, big crucibles need same as your setup, i think
and got 25 kg old cell phones today and 30 kg p3 motherboards, soon going to start the fires! thanks again

 

[ashir]

another idea
i have 30 kg mixed ic's
pyrolise and incinirate, crush and magnatic saperation,
using flux
borax
soda ash
silver powder
silica
flourspar
without pbo
will this work ?

 

[kurtak]

another idea
i have 30 kg mixed ic's
pyrolise and incinirate, crush and magnatic saperation,
using flux
borax
soda ash
silver powder
silica
flourspar
without pbo
will this work ?

Per the underlined - the short answer is yes

I don't have time today to post more details to help you on the right path

I will try to post more details tomorrow

If I am unable to post tomorrow - I will post this week end

Kurt

 

[ashir]

thanks kurtak. i like to use a collecter metal out of lead. so answer is bismuth, silver, copper( some use zn and al about which i have no knowledge)
bismuth is expensive (13 dollars per lb) and also a cupalation is necessary!
copper is good if copper cell is ready to work or it will take mor nitric
silver is batter (as i think) because it take less nitric, also can be recycled with silver cell.
both cells are out of my range because i just know basic about them! but i want your guide about using silver as collector. ( i will only use to recyle mobile boards, ics from motherboards and mlccs)
i am waiting for your reply!

 

[kurtak]

another idea
i have 30 kg mixed ic's
pyrolise and incinirate, crush and magnatic saperation,
using flux
borax
soda ash
silver powder
silica
flourspar
without pbo
will this work ?

ashir


Yesterday I spent a couple hours working on typing a post to provide you with more details - & them some how I accidently deleted it - sorry about that


That said - per the underlined - with 30 kg of IC chip it is not as simple as pyrolyze/incinerate, crush magnetic separate & then smelt the remaining ash


incinerating 30 kg of IC chips is going to give you "about" (plus/minus) a five gallon bucket (20 liter bucket) of ash with a "very small" amount of gold distributed in that bucket of ash (by comparison gold to ash)


smelting that much ash is going to take A LOT of both flux & collector metal along with having to run MANY loads (a load being the amount of ash - flux - & collector melt you can "safely" put in the crucible for each smelt run)

Edit to add; - the result is going to be that you end up with a "Very Small" amount of gold tied up in A LOT of collector metal

in order to have any real degree of success in smelting - you NEED to work that bucket of ash down to a "concentrate" --- that means you have to wash off - as much of the ash as possible - the more the better

So - you "need" to set up some kind of method for washing the ash off - & doing so without washing gold off along with the ash - which is likely going to happen if not done right (meaning it is very much possible to wash off/lose gold in this part of the process if not done right

This is all the time I have right now to post - but will try to post more in coming days

Kurt

 

[ashir]

thanks kutak, i open bookmark hundred of times today to get words form you!
concentration requires alot of perfection and experience, that i am not able!
and even no one can do this for me here!
its what happen today here,
i was looking someone to prepare a con mold for me, and no one in the market agree ! because
one said , its a mind using idea and i do not want use my mind
i ask him that i will mark the iron sheet and you just cut and weld it.
he ask me for 4 dollars to pay, i pay 5 dollars, 1 dollar to eat some thing that increase the capabality of his mind.
alot alot difficulties to prepare equipment! no one can make tongs even they see your setup picture, even i describe them !!!!!!
well washing ash will be next task to me as i want circulate the money i invested.
i know it will a time consuming and also more flux required but fluxes are cheap here, time is also not a matter because guys work in field regularly to collect scrap and saperate it. i am free to work !
i am just looking for your further guide. thanks again

 

[ashir]

another idea
i have 30 kg mixed ic's
pyrolise and incinirate, crush and magnatic saperation,
using flux
borax
soda ash
silver powder
silica
flourspar
without pbo
will this work ?

ashir


Yesterday I spent a couple hours working on typing a post to provide you with more details - & them some how I accidently deleted it - sorry about that


That said - per the underlined - with 30 kg of IC chip it is not as simple as pyrolyze/incinerate, crush magnetic separate & then smelt the remaining ash


incinerating 30 kg of IC chips is going to give you "about" (plus/minus) a five gallon bucket (20 liter bucket) of ash with a "very small" amount of gold distributed in that bucket of ash (by comparison gold to ash)


smelting that much ash is going to take A LOT of both flux & collector metal along with having to run MANY loads (a load being the amount of ash - flux - & collector melt you can "safely" put in the crucible for each smelt run)

Edit to add; - the result is going to be that you end up with a "Very Small" amount of gold tied up in A LOT of collector metal

in order to have any real degree of success in smelting - you NEED to work that bucket of ash down to a "concentrate" --- that means you have to wash off - as much of the ash as possible - the more the better

So - you "need" to set up some kind of method for washing the ash off - & doing so without washing gold off along with the ash - which is likely going to happen if not done right (meaning it is very much possible to wash off/lose gold in this part of the process if not done right

This is all the time I have right now to post - but will try to post more in coming days

Kurt

i have no idea on concentrate the ashes ! what will be the best way to wash off ashes without loosing pm's

 

[kurtak]

i have no idea on concentrate the ashes ! what will be the best way to wash off ashes without loosing pm's

ashir

There are a number of different ways to concentrate your chip ash

Examples - panning with a gold pan - using a blue bowl - sluice box/miller table - shaker table - I have even used 5 gallon (20 liter) buckets

Regardless of the method you use what is important is learning how to do it "without" washing off some of the gold bonding wires when washing the ash off because when washing the ash off you can wash some of the gold off with the ash if not done right

Also the method you choose depends somewhat on the amount of ash you are trying to concentrate - AND - how often you intend to do it

You said you have about 30 kg of chips to process - that's a lot of ash to try to concentrate


So my question is --- how often do you plan to process batches of (plus/minus) 30 kg of chips


Kurt