Assorted pins soaked in muratic acid w/ sub-zero

Can any one tell me how best to proceed with an assortment of loose pins which i have had soaking in Muratic acid and sub-zero for about a week? when i stir them most but not all appear to have been stripped of their gold. I am thinking filter it and neutralize my acid filter it and then add precipitate and drop the gold maybe ???

Sub Zero is just Sodium Nitrate.First off this solution is not capable of "stripping"the gold off of pins.You have made Poormans AR.This will simply dissolve everything,then you will need to preciptate your pm's.
Was there any reaction after you added the subzero?If not then you will need to warm the solution a little to help it get kick started.
What was the volume of pins,acid,and sodium nitrate that you used?

untill all of the pins are in liquid solution state , your gold will plate back out of solution to any remaining copper metal of the pins. using this method is only complicating a simple task.

2 pounds of pins+2 cups of muratic acid and 3 tablespoons of sub zero it is a lime green color now and not much of a reaction other than the acid appeared to oxidize the pins and dissolve the sub-zero when added. I a guessing it would be best to put it on the hot plate and cook the crap out of it a few times ??? thanks. I went with this approach because it was truely an odd assortment of pins that were left over odds and ends after air-chiseling a bunch of drives and mother boards that type of thing with all the plastic and such removed. It seemed obsurd to try and sort out the individual pins to be honest and that was my reason for such madness. I have been stirring it about once a day figured that if i wasn't getting anywhere at this point i would put the coffee pot on the hot plate next and cook the snot out of it next as everything else seemed a bit pointless in terms of another aproach.any advice will recieve my sincerest of thanks.

Cursed said:

2 pounds of pins+2 cups of muratic acid and 3 tablespoons of sub zero it is a lime green color now and not much of a reaction other than the acid appeared to oxidize the pins and dissolve the sub-zero when added. I a guessing it would be best to put it on the hot plate and cook the crap out of it a few times ??? thanks. I went with this approach because it was truely an odd assortment of pins that were left over odds and ends after air-chiseling a bunch of drives and mother boards that type of thing with all the plastic and such removed. It seemed obsurd to try and sort out the individual pins to be honest and that was my reason for such madness. I have been stirring it about once a day figured that if i wasn't getting anywhere at this point i would put the coffee pot on the hot plate next and cook the snot out of it next as everything else seemed a bit pointless in terms of another aproach.any advice will recieve my sincerest of thanks.

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You are trying to dissolve too much material with too little fluid.

Bump your solution volume up to about 3 liters.

Cursed
were you trying to do HCl-Peroxide, thinking that subzero was an oxidizer like peroxide or bleach? Just trying to understand your motivation here.

As was stated by mic, you have made an inprecise version of Poor Man's AR - Lazersteve's recipe for which follows. This is the updated one. Notice that, as mic advised, heat is required for the process to work effectively, needs to be monitored closely, and additions of nitrates should be incemental. As your acid becomes saturated, it needs to be decanted, filtered & tested with stannous for gold content, & replaced with fresh.

As BR 007 stated, you have way too little solution for the amount of copper & nickel that will be dissolved. Boiling the crap out will just hasten the expulsion of acid, unless your container is covered, and you'll also hasten the build-up of salts, which is no fun either. You will boil in this process but it is controlled & precise.

Once i figured out what was going on, & since my ADD/OCD finds waiting (what seems like) days & days for crockpot- HCl to work agonizing, it has become my method of choice for pins, since I don't have the quantity of material either that would justify separating steel pins from Kovar or brass.

Again: THIS IS LAZERSTEVE'S RECIPE, for processing the pins from ceramic CPUs. i have it saved on my PC; it was easier to cut and paste it than to find the thread again. Maybe someone can go right to it.

Processing ceramic cpus
Here's how I proceed with Poor man's AR:

1.Remove lids (top and bottom) from ceramic cpus using MAPP gas.
2.Add cpu's into large beaker or coffee pot.
3.Fill with HCl (31.45% approx 10 M). Add just enough to cover the cpus.
4.Add and equal volume of tap water
5.Place small ceramic saucer on top of pot to prevent vapor from escaping.
6.Heat to just below boiling.
7.Add in 2 teaspoons of sodium nitrate.
8.Boil for 30 minutes or until brown fumes are no longer visible.
9.If salts form pour off dark acid through tight filter and start at step 3 above. Filter may contain gold foils or powder.
10.Repeat steps 6 and 7 until all metals are dissolved.
11.Remove ceramic saucer and let the solution evaporate down to 25% of it's original volume, or until salts form.
12.Add fresh HCl to expel nitric as brown vapors.
13.Repeat steps 9 and 10 two more times.
14.Dilute with equal volume of tap water.
15.Filter through packed funnel under vacuum until 100% free of sediment and suspended particles.
16.Add Sodium Meta Bisulfite to precipitate gold as brown powder.
17.Let settle and siphon liquid off brown powder.
18.Add enough water to cover brown powder.
19.Repeat steps 17 and 18 two more times.
20.Add enough HCl (32% 10M) to cover brown powder.
21.Boil HCl with brown powder until color of HCl no longer darkens.
22.Repeat steps 17 and 18 two more times.
23.Slowly dry gold in beaker by shaking beaker over medium heat until the gold powder moves freely about the beaker it's was precipitated in.
24.Transfer brown powder melting dish and heat to red heat (incinerate) DO NOT MELT!!!
25.Transfer incinerated powder to beaker and repeat process steps 3 to 21 on the brown powder.
26.Prepare melting dish as shown on my website melting videos.
27.Melt dry gold powder in properly prepared melting dish.

dtectr

Here's the link to the process:

Modified Poor man's AR

Use the version in the link as it has all of the updates that I have done to the process since I first posted it. Some of the corrections fixed errors to the step numbers, so it's important not to rely on copied and pasted data. A good example of this is the General Reaction list. I update this at least once a month so if anyone is working off of a copy of it, they are likely missing information I've added.

Archiving the information is nice for ease of access, but you lose the dynamic nature of the forum and miss all of the updates and improvements. This is why I advise that everyone learns how to find information here using the search functions. Also when posting be sure you include at least one completely spelled out version of any abbreviations in the post and include a unique set of 'keywords', so it's easy to find later. An example of using a keyword in a post is : using a term that is not common to a similar post (i.e. the word 'Modified' in the link above) and combinations of terms that pin point the topic of the post (ie General Reaction List).

If we all adopt good posting habits, the forum is much easier to search.

Steve

Excellent info, Steve. I, for one, was not aware of the frequent updates -
I know that takes a lot of time, but I'm sure I'll benefit from taking advantage of it.
The "keyword" should be placed where, for greatest benefit - in subject line, body, or etc.?
thanks again.
dtectr

I put them in the subject lines as well as the body of the post. I recall posts using these unique keywords I put in various types of posts.

When you post, think about what you would put in a search box if were searching for the post in Google and had to locate your exact post.

Steve