Washing process and no ice available.

[Aeon13]

Beautiful button sir!

 

[UncleBenBen]

Your FIRST button is 124.5g?!?!
Way to go autumnwillow!

I think I have button envy now!

 

[Aeon13]

Your FIRST button is 124.5g?!?!
Way to go autumnwillow!

I think I have button envy now!

True! My first button was 1.2 grams. 8)

 

[nickvc]

I don't know of one near you but a good cheap and fast service is available off these guys .
Guardian laboratories Midlands Ltd. they are in the UK fax 0121 359 7281 phone 0121 359 8233
Know the guys well they are very good and a gold assay is around $15 and they only need around 1/2 gram to work with, I think you can pay them by PayPal or cash but ask them, hope this is of use to you.

 

[autumnwillow]

Beautiful button sir!

Thank you. Feel free to visit my workshop anytime. Get your chemicals for free(as long as they are in small quantities) so you can get started. Just make sure you get a proper fume hood with scrubber. You should also read about waste treatment. Educate your miners and help them grow. They are doing most of the hard work so they deserve a good treat.

Your FIRST button is 124.5g?!?!
Way to go autumnwillow!

I think I have button envy now!

This button produced a lot of stains in my hand and my hood(I still need practice on the art of lab work and need to deal with the condensing of closed scrubber systems), as I was doing other work not related to refining, a lot of phone calls, etc. I had to remove my gloves often only to go back to the lab and forget my gloves. I even washed a 50% caustic containing beaker with my bare hand wondering why my hand feels hot. Good thing I was at the sink. If you will look at my hand right now, there's a gold chloride stain, nitric stain, h202 stain and caustic stain. In small amounts though. They still look presentable. Heh.

I don't know of one near you but a good cheap and fast service is available off these guys .
Guardian laboratories Midlands Ltd. they are in the UK fax 0121 359 7281 phone 0121 359 8233
Know the guys well they are very good and a gold assay is around $15 and they only need around 1/2 gram to work with, I think you can pay them by PayPal or cash but ask them, hope this is of use to you.

I live in Asia, so that won't work. I wonder if I could do the fire assay myself? I have access to a high precision balance and a furnace. Are there any other equipments required?

 

[Aeon13]

Thank you. Feel free to visit my workshop anytime. Get your chemicals for free(as long as they are in small quantities) so you can get started. Just make sure you get a proper fume hood with scrubber. You should also read about waste treatment. Educate your miners and help them grow. They are doing most of the hard work so they deserve a good treat.

I will definitely visit you sir. I will also read topics about waste treatment. Spot on sir about the miners, they are the hardest workers I've ever seen in my life. They do deserve better. I will do my best to help them in any aspect as long as I can.

I wonder if I could do the fire assay myself? I have access to a high precision balance and a furnace. Are there any other equipments required?

Looking forward to this sir autumnwillow.

Regards
Mohammed

 

[upcyclist]

Also, I though Platinum dissolves in nitric when alloyed with silver, this lot was from inquarted gold jewelry scrap. Or maybe the white powder is something else?

Did you ever figure this one out? If not, did you fully dissolve & then remove your silver from the nitric solution before adding HCl to make AR and dropping the gold? If you didn't, that white powder could be silver chloride. It'll form when the nitric is added because if there's silver left, it dissolves with the nitric, then reacts with the HCl to make AgCl. That in turn frees the nitrate, which then helps get your gold into solution. But it reacts with the silver first, because silver is more reactive than gold.

 

[Topher_osAUrus]

Also, I though Platinum dissolves in nitric when alloyed with silver, this lot was from inquarted gold jewelry scrap. Or maybe the white powder is something else?

Did you ever figure this one out? If not, did you fully dissolve & then remove your silver from the nitric solution before adding HCl to make AR and dropping the gold? If you didn't, that white powder could be silver chloride. It'll form when the nitric is added because if there's silver left, it dissolves with the nitric, then reacts with the HCl to make AgCl. That in turn frees the nitrate, which then helps get your gold into solution. But it reacts with the silver first, because silver is more reactive than gold.

When this happens, doesnt the silver chloride tend to be more grey than white?
-i thought my AgCl from ar was grey from precious metal contamination, but, i forgot that the sun will also make it more grey than white.

But is this an applicable statement when it is being. actively processed in AR?

Since the grey coloring (from light) is actually the chloride being turned back into silver metal, since the AR has free Cl, Would it be continually turning from metal to chloride salt(if an abundance of lught was there to convert?)

Sorry if my train of thought isnt that concise. I have family over, and they are more than distracting

Edit to recant my statement a bit

 

[nickvc]

My only other advice is to refine your metal twice using different precipitants which changes the possible drag down effect, if you have no access to fast cheap assays it's the only way to be sure of the quality of your finished product.
GSP or 4metals can advise on assays in house but the problem with fine metals is that you have to work almost backwards from what little I understand, I'm sure they can explain it better.

 

[autumnwillow]

Also, I though Platinum dissolves in nitric when alloyed with silver, this lot was from inquarted gold jewelry scrap. Or maybe the white powder is something else?

Did you ever figure this one out? If not, did you fully dissolve & then remove your silver from the nitric solution before adding HCl to make AR and dropping the gold? If you didn't, that white powder could be silver chloride. It'll form when the nitric is added because if there's silver left, it dissolves with the nitric, then reacts with the HCl to make AgCl. That in turn frees the nitrate, which then helps get your gold into solution. But it reacts with the silver first, because silver is more reactive than gold.

Okay let me explain the process I did. I was doing this in a newly built fume hood and vacuum scrubber setup. You can see the poorly designed hood here: http://goldrefiningforum.com/phpBB3/viewtopic.php?f=40&t=23529

When I first processed the inquarted gold in nitric diluted with H202/distilled water. I never turned the heat up because I was testing the scrubber whether it could scrub properly or not. This process took almost 4 hours until I decided to decant the liquid and smashed the corn flakes to powders so the nitric can attack the base metals further. Note that not all of the corn flakes were turned into powder/mud, some were a bit hard to smash so I left them as is. I then repeated the process with nitric/h202 distilled water. This time under high heat. I then washed multiple times with distilled water, boiled it in distilled water then washed again multiple times with distilled water until the wash liquid was clear.

I then add about 500ml of h202/distilled water, 500 ml of HCL, separate additions of 120ml nitric. After the digestion stopped, I diluted the solution and added sulfamic acid dissolved in hot distilled water, mixed the solution, added more until there was no fizzing, then just a little bit more. I then filtered the solution, which took hours because I had to change filter papers as they were clogging up. Diluted the solution further then added 120g SMB dissolved in distilled water to the solution.

Note also that I do not think the heat really goes up because of the fume hood design. The room is at negative pressure, I was able to check this by shutting the door of the room and feeling the small gaps on the sides of the door, there was a pressure of air being sucked in the room. With this I think that the heat is being sucked out by the fume hood/scrubber setup. I will turn off the fume hood exhaust next time when vacuum scrubbing digestions.

From my understanding, platinum only dissolves under very high heat. My nitric digestion was only under high heat on the second set and my AR digestion was never under high heat.

One way I could check is to melt the powders. I have about 3-4 of this filter paper. Now I highly doubt that this is silver chloride, but melting it to check (if this is silver chloride) would produce chlorine gas which is not good for me. Another method would be to try and convert the powders as if they were silver chloride but I'm not sure if the silver chloride conversion techniques would have different reactions to this suspected PGMs which would further complicate things. I will try to take a sample and do it in a test tube. Maybe next week, as I have other jobs not related refining to do.

 

[nickvc]

If you inquart with silver the PGMs will go into solution with the silver, so test your nitric solutions for PGMs, some may also go into your AR again test with stannous.
If you do have PGMs in your nitric solutions then you have to make a decision of the route to follow.
You can convert the silver to chloride decant and filter the solution off and then cement the values using copper, in my opinion the easiest route.
You can cement all the values with copper and put the silver and any PGMs cemented through a silver cell and collect the values from,the slimes, not so easy and a pain dealing with the slimes.
If you have values still in your AR either add to your stock pot or cement with copper.
I know I repeat this regularly but be very careful with PGMs in solution or as chlorides as they are highly toxic and dangerous.

 

[autumnwillow]

If you inquart with silver the PGMs will go into solution with the silver, so test your nitric solutions for PGMs, some may also go into your AR again test with stannous.
If you do have PGMs in your nitric solutions then you have to make a decision of the route to follow.
You can convert the silver to chloride decant and filter the solution off and then cement the values using copper, in my opinion the easiest route.
You can cement all the values with copper and put the silver and any PGMs cemented through a silver cell and collect the values from,the slimes, not so easy and a pain dealing with the slimes.
If you have values still in your AR either add to your stock pot or cement with copper.
I know I repeat this regularly but be very careful with PGMs in solution or as chlorides as they are highly toxic and dangerous.

I have already cemented my nitric waste. I have forgotten to drop the Pd first though, I'll do that on the next batch. It also cemented faster than I could filter that grey powder. The problem that I have now is what is in the filter paper? This filter paper contents are the solids before I precipitated the gold.

 

[Topher_osAUrus]

Also, I though Platinum dissolves in nitric when alloyed with silver, this lot was from inquarted gold jewelry scrap. Or maybe the white powder is something else?

Did you ever figure this one out? If not, did you fully dissolve & then remove your silver from the nitric solution before adding HCl to make AR and dropping the gold? If you didn't, that white powder could be silver chloride. It'll form when the nitric is added because if there's silver left, it dissolves with the nitric, then reacts with the HCl to make AgCl. That in turn frees the nitrate, which then helps get your gold into solution. But it reacts with the silver first, because silver is more reactive than gold.

Okay let me explain the process I did. I was doing this in a newly built fume hood and vacuum scrubber setup. You can see the poorly designed hood here: http://goldrefiningforum.com/phpBB3/viewtopic.php?f=40&t=23529

When I first processed the inquarted gold in nitric diluted with H202/distilled water. I never turned the heat up because I was testing the scrubber whether it could scrub properly or not. This process took almost 4 hours until I decided to decant the liquid and smashed the corn flakes to powders so the nitric can attack the base metals further. Note that not all of the corn flakes were turned into powder/mud, some were a bit hard to smash so I left them as is. I then repeated the process with nitric/h202 distilled water. This time under high heat. I then washed multiple times with distilled water, boiled it in distilled water then washed again multiple times with distilled water until the wash liquid was clear.

I then add about 500ml of h202/distilled water, 500 ml of HCL, separate additions of 120ml nitric. After the digestion stopped, I diluted the solution and added sulfamic acid dissolved in hot distilled water, mixed the solution, added more until there was no fizzing, then just a little bit more. I then filtered the solution, which took hours because I had to change filter papers as they were clogging up. Diluted the solution further then added 120g SMB dissolved in distilled water to the solution.

Note also that I do not think the heat really goes up because of the fume hood design. The room is at negative pressure, I was able to check this by shutting the door of the room and feeling the small gaps on the sides of the door, there was a pressure of air being sucked in the room. With this I think that the heat is being sucked out by the fume hood/scrubber setup. I will turn off the fume hood exhaust next time when vacuum scrubbing digestions.

From my understanding, platinum only dissolves under very high heat. My nitric digestion was only under high heat on the second set and my AR digestion was never under high heat.

One way I could check is to melt the powders. I have about 3-4 of this filter paper. Now I highly doubt that this is silver chloride, but melting it to check (if this is silver chloride) would produce chlorine gas which is not good for me. Another method would be to try and convert the powders as if they were silver chloride but I'm not sure if the silver chloride conversion techniques would have different reactions to this suspected PGMs which would further complicate things. I will try to take a sample and do it in a test tube. Maybe next week, as I have other jobs not related refining to do.

In AR, yes Pt requires very high heat, but when nuking your inquarted material with nitric, if platinum is in minimal % of the makeup, it will readily go into solution with silver and Pd. Which then must be recovered by cementing (easiest way...im sure you could go about it differently, but...)

 

[nickvc]

A picture of that filter and its contents will help so we can advise further but if you melted all your scrap together when you inquarted it's possible any larger solid pieces of platinum did not melt into the mix fully or even at all, post that picture and let's see what's happening.

 

[autumnwillow]

A picture of that filter and its contents will help so we can advise further but if you melted all your scrap together when you inquarted it's possible any larger solid pieces of platinum did not melt into the mix fully or even at all, post that picture and let's see what's happening.

The filter is at page 1 nickvc.

 

[nickvc]

Looking at the picture it looks like silver chloride, if you can't see any true metallic flakes or pieces the chances are the PGMs went into solution in your nitric digest, you can gently incinerate the filter papers and put the remains in a beaker wash with ammonia to remove any silver chloride and then check to see if there is any material left, if there is simply dissolve in hot AR, if you do wash this powder with ammonia makes sure to add some HCl after to avoid explosive hazards.
If you do need to dissolve in AR you can then use stannous to see what you have.

 

[autumnwillow]

Looking at the picture it looks like silver chloride, if you can't see any true metallic flakes or pieces the chances are the PGMs went into solution in your nitric digest, you can gently incinerate the filter papers and put the remains in a beaker wash with ammonia to remove any silver chloride and then check to see if there is any material left, if there is simply dissolve in hot AR, if you do wash this powder with ammonia makes sure to add some HCl after to avoid explosive hazards.
If you do need to dissolve in AR you can then use stannous to see what you have.

Wouldn't the silver chloride produce chlorine gas upon incineration or does this chlorine gas only happen when the material is melted?
How do you recover the silver chloride dissolved in ammonia? Add HCL then cement with Cu?

 

[nickvc]

Virtually all incinerations produce nasty fumes so decent extraction is advised whenever you do it.
You could just put water through the filter several times to remove as much acid as possible and then place your filter whole into a beaker and wash with ammonia which will remove any silver chloride, as I said you need to add HCl after to your ammonia which will produce silver chloride again.
Whatever is left after the ammonia wash is now visible either in the beaker or on your filter paper, wash off any residues from the filter paper with your water bottle and put the filter with any others you have to treat later, if you have any metallics they should now all be in the beaker so just dissolve in AR and test with stannous.

 

[g_axelsson]

Silver chloride doesn't break down when melted, it starts to give off silver chloride fumes.

There are several methods to recover silver from silver chloride, check the library, read Hoke and search the forum... hint, cementing on copper isn't one of them.

Göran

 

[autumnwillow]

Virtually all incinerations produce nasty fumes so decent extraction is advised whenever you do it.
You could just put water through the filter several times to remove as much acid as possible and then place your filter whole into a beaker and wash with ammonia which will remove any silver chloride, as I said you need to add HCl after to your ammonia which will produce silver chloride again.
Whatever is left after the ammonia wash is now visible either in the beaker or on your filter paper, wash off any residues from the filter paper with your water bottle and put the filter with any others you have to treat later, if you have any metallics they should now all be in the beaker so just dissolve in AR and test with stannous.

Thank you for the advice, I really hate the ammonia smell, I have a technical grade one which I dilute to 3% content. I dislike opening the 1 gallon bottle even under the fume hood it stinks.

I haven't bothered to put filter papers in any of my AR process as I think this would contaminate the gold. What happens to the filter paper when you put it in AR?

Silver chloride doesn't break down when melted, it starts to give off silver chloride fumes.

There are several methods to recover silver from silver chloride, check the library, read Hoke and search the forum... hint, cementing on copper isn't one of them.

Göran

There are a lot of methods, Lou's method, saltlakemetals method, formaldehyde method, etc. I find Lou's method to be the best if it wasn't for the formaldehyde toxicity.
To be honest with you, I have read Hoke's book so many times that I think it is already outdated and the processes there generate too much waste. I already have about 25gallons of copper nitrate, 5 gallons has already been processed with iron (which is a pain to do). I would go for HCL addition to make silver chloride this time, then just process the solution remaining in the stock pot. The remaining 20 gallons, I'll just save it and I believe I could use it somewhere sometime.

Keita