Drop it like it's Hot (chemistry questions about dropping the gold)

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snoman701

Well-known member
Joined
Oct 8, 2016
Messages
2,108
Location
SE MI
Multiple questions about the drop.

1) I did two today using SMB. The first...big chunks of gold. The second...slow, fine gold.

2) What are the situations that produce big chunks vs the fine stuff that takes forever to settle?

3) Also...is dropping with SO2 really as simple as just putting a hose in the beaker and letting it bubble? Does it work on excess nitric as well?

4) This is so much fun I'm thinking about building an SO2 generator. Is anyone using one? Is it really necessary to bubble the SO2 through concentrated H2SO4...I mean, it's being bubbled in to an aqueous solution.

5) Finally, does my copperas look right? It wouldn't go in to solution with water, so I added sulfuric acid to it and heated it. It did this really cool boiling thing where the whitish layer would boil underneath the sulfuric acid...then when cooled it did this. The whitish layer SEEMS to be solvent in the water/sulfuric above...if you break in to it and start stirring. (picture is on cell phone, so I have to post this, then post picture)

Both beakers are essentially the same, just two batches.
 
Here we are
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Hmmmm. That doesn't look like any gold I have ever seen after an SMB drop.
Did you remove the base metals before the drop? What was your process prior
to the addition of SMB?
 
glorycloud said:
Hmmmm. That doesn't look like any gold I have ever seen after an SMB drop.
Did you remove the base metals before the drop? What was your process prior
to the addition of SMB?


I think thats his "copperas" dissolving, and it doesn't look right.
I kind of see a slight green tinge to the liquid, but, there is something wrong with it... It looks sickly. :lol:

Where did this copperas come from? By chance, is it anhydrous ferrous sulfate? The good green crystals of copperas have water in their formula.

I would like to see your gold though, too! ...instead of just showing us your gold laden processors :wink:
 
Sno I'm going to be politely blunt.

The time to start thinking of building S02 generators, or any other equipment is when you've grasped the basics and understand exactly what's going on in your solutions to the point where you can control a reaction, and drop gold cleanly. Now it takes guts to post up those pics and I take my hat off to you for doing so but now is the time to step away from all the other ideas, all the equipment plans and learn to refine gold from the floor up.

When you've got that, and can do it repeatedly then you can think about other things.

Typed with the best of intentions

Jon
 
Fairly said....appreciate the candor!

Here's another 2 grams of dirty powder topher.

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Yeah, so, I was considering being politely blunt yesterday and luckily Jon beat me to it.

You appear to have some awesome scrap to process, but at the moment you are wasting it through inexperience.

Be super careful with Sulfuric and water in the same general area.

As far as your SMB drops - The big chunky stuff that settles fast is a clean solution that is giving you clean gold. The fine crap that takes days to settle is a dirty solution and is going to give you dirty gold. Did you leave the solutions to stand for a day or two before dropping the gold to allow chlorides to settle on the bottom ? Did you add a few drops of Sulfuric to the solution to precipitate out any lead before dropping with SMB ?
 
So the copperas that I posted exists like that because that which I ordered was oxidized. It started out all brown. The liquid portion is a mixture of water and 10% or so sulfuric acid. There is a layer that seems to be quality crystals, and I've been digging them out and trying to dissolve them (successfully) and recrystalize them in another dish. As I do this, the layer seems to regenerate some.

I'm thinking that it's just lacking enough water, but also because it didn't have the right amount of water to begin with, it didn't slowly crystalize out.

I've been using SMB to drop my gold as of now, which has been working for me. To be flat out honest, I'm still using dirty glassware. I'm still trying to figure out what is best, what volumes are best, what is most comfortable to use, etc. But dishes are pretty difficult as well, being on a well & septic, I don't want ANY of my dishwater going down the drain. I usually pre-wash it in the shop, then only when it seems clean there, will I take it in to the "kitchen" to wash it.

So there are a lot of things besides myself that are working against me.

I can't tell you how much I miss my lab...a proper hood, a heavily ventilated room on top of it...and I didn't even have the neighbors trying to figure out what that guy is doing standing outside with a hotplate & lab glass.
 
kernels said:
Yeah, so, I was considering being politely blunt yesterday and luckily Jon beat me to it.

You appear to have some awesome scrap to process, but at the moment you are wasting it through inexperience.

Be super careful with Sulfuric and water in the same general area.

The sulfuric is "just" battery acid. I haven't been able to find gauntlets locally, so I haven't started using concentrated sulfuric.

I'm not processing anything "nice" at this time...for the most part.

Yesterdays gold was the result of me saying "I give up"....so i threw some gold capped cdips in to a beaker and dissolved everything in AR. Up until that point, I wasn't really certain that I had a reasonable quantity of gold in any of my solutions. They tested positive via stannous, but that doesn't mean it's going to be a good drop. That was the first drop that actually dropped. The others have mostly taken cementation.

When I started, the only gold I had was my wedding ring...and while I have an understanding spouse, she's not THAT understanding....so even working through the basic exercises in Hoke was impossible. I am really just now feeling like I'm getting there....plus, now I've got enough gold that I can do the exercises, and hold myself accountable. The problem with E-scrap is it's soooo variable.

This powder is the result of my stock pot....where all the previous mistakes went. Added to it was a few assays of some heavily plated copper parts.

What is shown, is just a drop in the bucket of my nicer stuff. I bust my butt to find this stuff, and I pay for it...but there is enough data on this site that I'm comfortable with the prices I pay, if I'm careful. I figure if I keep my cash price below boardsort, and concentrate on things that are easier to process like ceramic processors, I'll be mostly safe. Plus, if I ever need to cash out, I can just drive it all out to Cleveland and dump it. Though at the rate it's accumulating, I may be better off selling direct to one of the batch processors like SIPI.

As far as your SMB drops - The big chunky stuff that settles fast is a clean solution that is giving you clean gold. The fine crap that takes days to settle is a dirty solution and is going to give you dirty gold. Did you leave the solutions to stand for a day or two before dropping the gold to allow chlorides to settle on the bottom ? Did you add a few drops of Sulfuric to the solution to precipitate out any lead before dropping with SMB ?

Thank you! This is the knowledge that I find difficult to locate. So if I've got a clean, balanced solution, I should always see nice grain sizes then...and vise versa, if it's fine ugly gold, it's likely coming from a dirty solution. In this case, this was the first refining of the stock pot AR, and it was dark dark green.

I let them stand overnight.

I did not add sulfuric...concentrated or dilute?
 
anachronism said:
Why do you have sulphuric acid present in your copperas?

To reduce the oxidized copperas so that it would again be soluble in water.

I did this on the small scale...I mixed a couple table spoons of oxidized copperas with sulfuric acid to be around 10% by volume. I then heated and stirred the solution. It all turned the pretty green color. Upon addition of MORE powder, I got that ugly mess.

Addition: note that the white layer beneath the intermediate layer IS crystallized, it's just not the pretty green crystals. They are more linear.

The other answer is Butchers statement that leaving the copperas crystals submerged beneath a sulfuric acid layer will keep them from oxidizing.
 
snoman701 said:
I let them stand overnight.

I did not add sulfuric...concentrated or dilute?

Excellent, sounds like you are doing better than your top post suggested.

Have you noticed any white powder settling out of your solution when standing overnight ? I find it best to siphon about 3/4 of the solution after any white powder settles for a day or so, the other 1/4 goes into a larger holding bottle where pregnant solution accumulates over time while all the white powders from all the individual batches settle in the bottom of the bottle. I hope this makes sense, Even I find it hard to read!

You want your solution to be 100% crystal clear before you drop with SMB, don't worry about the color too much.

I don't think the concentration of the Sulfuric makes a big difference, but I may be corrected by someone more knowledgeable. I use Sulfamic acid to convert excess Nitric in my solution to Sulfuric. This is usually enough to precipitate any lead, so clean dilute Sulfuric should also work. Add the Sulfuric (or denoxx with Sulfamic) and then let the solution stand for a day.

I haven't tried myself, but read a few times that making copperas from scratch is pretty simple, I believe you just need some iron from the laminations of a transformer and Sulfuric acid.

Occasionally I still get a dirty drop where the gold does not 'clump' or settle fast. In these cases I leave it to settle for a couple of days, then do a second refine and pay more attention to separating out the clear solution from the settled white / grey powder.
 
kernels said:
Have you noticed any white powder settling out of your solution when standing overnight ? I find it best to siphon about 3/4 of the solution after any white powder settles for a day or so, the other 1/4 goes into a larger holding bottle where pregnant solution accumulates over time while all the white powders from all the individual batches settle in the bottom of the bottle. I hope this makes sense, Even I find it hard to read!
No, not making sense.

Once I have a pregnant solution, I denoxx with sulfamic. I then dilute this to at least two times the volume, adding ice to bring the temperature down. Once the ice is completely melted, I add my SMB, wait about fifteen minutes and test with stannous. If test was negative for gold, I let it sit overnight.

Once it is settled, I pour off (through a filter) supernatant liquid, minding to keep a steady hand and a slow pour to keep the gold from moving. I then wash in distilled water as many times as it takes for me to be confident that it's pretty clean. If I'm using a beaker, that could be three....if a canning jar, as I had to earlier, it was a lot.

Supernatant liquid is transferred to stock pot to sit. Stock pot is rarely moved from it's place on the bench...I drain by siphoning off all but the last inch.

The only white powder I remember was when I was still using coffee filters. I attributed it to the glass frit they glued cdip ic's together with...and I could never seem to get it to filter out. Also, silver chloride, which is in a seperate bucket.
 
snoman701 said:
Once I have a pregnant solution, I denoxx with sulfamic. I then dilute this to at least two times the volume, adding ice to bring the temperature down. Once the ice is completely melted, I add my SMB, wait about fifteen minutes and test with stannous. If test was negative for gold, I let it sit overnight.

OK, so that is likely part of your problem, next time, after denoxxing with Sulfamic let the solution sit overnight before you drop the gold out. There will be a thin layer of white powder sitting on the bottom of your beaker. This is what is contaminating your gold.

What is happening is the Sulfamic is turning excess Nitric into Sulfuric, the Sulfuric is causing lead to precipitate out, but you are then immediately dropping the gold, so your gold powder is full of lead chloride.
 
So, the 'holding bottle' that I was trying to explain before, is just a bottle where the left over pregnant solution and white powder from many individual batches goes after I have siphoned off the top 3/4 of the pregnant solution. The powder settles in the bottom of the bottle and when the bottle starts getting full (usually about once a month), I once again siphon off the pregnant solution leaving some solution and the white powder in the bottle.

I use a 2L glass bottle for my holding bottle, but you could use any suitable container you have available. The key to not have any fine powder in suspension when you drop the gold. The solution must be 100% Crystal Clear!
 
Ok....yeah, I haven't had any problem with clear solutions since I switched to proper filter papers. After I filter it, I use a lot of distilled water to flush the pregnant solution from the filter paper. Then once done, the filter paper goes to my filter "bucket" for an incineration at some point.

I've been very careful to make sure that I only drop (or cement) clear solutions.

I have a similar bottle that I use for silver chloride. I let it settle, then siphon off excess.
 
Filter papers wont catch the super fine powder, and washing the filter paper after filtering is just helping more of the fine powder make it through the filter. Using very good lab filter paper and a vacuum setup is better than coffee filters, but still no match for waiting a day for the powder to settle.

I keep saying the same thing, but somehow the message is not getting through. Just try leaving a solution sitting for a day after denoxxing (before dropping the gold), you will see the fine layer of sediment settle.

Your solution appears clear, but likely has very fine powder in suspension. Only experience will teach you the difference between a solution that is 100% clear and one that is not.
 
If you can read a newspaper through it clearly or shine a laser through it clearly then it's clear. 8)

Whatman number 1 papers will take a solution to crystal clear.
 
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