Aqua Regia Problem please help

[lukeduke077]

I am a newbie to doing this. Just a young guy 32 trying to run my own business. I sell antiques for a living. Mostly watches and jewelry. So I end up with a lot of scrap G.F. My thought was to refine my scrap. So I could accure some saving for future investments. I finally spent the money to purchase all the things I need to refine my scrap.

Yesterday me and my friend spent 14 hours setting up or lab. Then trying to make our first batch of aqua regia. The day time was beautiful yesterday. So we did a nitric leech on some watch caps.

Which had a weight of 177 Grams. The process seemed to go well except we might of poured a little of our gold off when filtering. It was starting to get late . So I added about 50 grams of scrap GF Watch cases. I did not leech the watch cases. I added them to make sure we could recover something tangible.

I know hindsight is 20/20 and that was a mistake. I measured a 1 Nitric to 4 Hydrochloric acid ratio. I based my numbers on 227 grams. So I went 300 ML of Hydrochloric to 75 ML of Nitric. I went a little heavy as per our leaching. I had been a little light on the acid ratio. l I am not sure what a good formula to calculate the proper ratio would be. I was going to use 4.5 ML per gram of scrap. That seemed to be a large amount of acid for pre leeched items.

We again attempted to work with hot water in a bowl. Not boiling water though. Using that bowl of warm water. We put our aqua regia jar into the water. I then added the acids. I got a initial strong reaction. Which then rapidly dissipated to a very slow reaction. As the reaction slowed we added more warm water.

To clarify we wanted to use a flame to heat the water under the regia. With the regia being raised off of the boiling water. So that the steam would heat the regia. However our stove did not arrive in time. We should have it this week.

Getting back to the regia. As the night progressed into darkness the process was very slow. The weather took a drastic drop in temperature. So it was really hard to keep the warm water on the regia. We keep heating water to keep the regia warm. I think the chilly temp was affecting the process.

I even followed videos I had seen online. Which told me if the reaction stops to add small amounts of more nitric. So I added 5 ML and 3 ML of Nitric at water changes toward the end. Which allowed the reaction to continue very slowly. The last time we changed the water at the end of the night ( around 12:00Am Est). the jar the regia was in cracked on us. Nitric affect was minimal at this point.

That is when we finally ended the process. As we did not feel it would be safe to continue any longer. What we had was watch cases and steel watch band caps still intact. However the Nitric had stopped working at least to the naked eye. All the gold appeared to be dissolved off of the material. As the base metals were all very chewed up.

The solution was very reddish brown. Solution also had a lot of white ash in the bottom. We took the solution and slowly began to filter the regia off. We had to get the acids out of the cracked glass jar.

We made a filter for our funnel. As we started to filter the reddish brown solution. the white sandish sludge keep clogging the filter. I would really like to know what this material is ? I also would like to know what other metal elements that tend to be present in gold fill as well.

We also were seeing coarse pieces of gold flake. Which the white material clogging the filter was obstructing from going thru. What should I do in this situation. We were very cold at this point. We tried to wash the gold on thru. The color going thru the filter was a very reddish brown color. The powder also got thru the filter into the final solution.
We were unsure as to what to do next. As we were seeing rainbow gold everywhere. We seen it in the cracked jar. We rinsed the material that was unbroken down and placed it in a jar. We were seeing gold all over that jar. The stuff that splashed went into a bucket below and we felt like we were in Alaska. So we knew we had liquored gold. I will admit we had a bit of gold fever at this point.

We went ahead and added Urea to the solution . Trying to neutralize the Nitric. There was some bubbling and then nothing with more Urea added. So we decided to test the regia solution for acid PH. The Solution was registering a PH of 12. So nothing is neutralizing the nitric. It was 5 AM at this point so we called it a night. I know I have totally botched the process.

My next step as we saved all the diluted solution. At least to my simple science mind. Is to wait for our burner. Once it arrives I was thinking that I would place solution back into beaker. Trying to use steam to cook the nitric out of the solution. However I still have all this powder residue & a very dark solution. Which on the bottom I can see gold flakes & sludge. I do not know if it can even be salvaged.

But I damn sure do not want to throw it away. Should I add more Hydrochloric to try and balance the 2 acids. How do I get rid of the bad stuff. Yet allowing me the ability to keep the silver and gold. Does this solution produce salts ? Why is the solution so dark ? I know I am a novice at this.
Ok I have received 3 critical posts. I am just looking for some help folks. I have a bucket of acid with gold and other crap in it. I need to finish this process . Can someone provided me something positive information regarding this subject thanks Luke

 

[jimdoc]

Sounds like you are rushing things. And not studying enough, especially about safety.

Jim

 

[jimdoc]

Writing one long paragraph makes it really hard to read and understand what you are saying.
You may want to remember that for future posts.

Jim

 

[goldsilverpro]

It takes too much effort to read that 1500 word paragraph. It's about the worst I've seen. Can't you break it down to 10-15 understandable paragraphs? As you wrote it, I can't imagine anyone wanting to wade through it. I surely won't.

 

[4metals]

Luke,

Welcome to the forum. first, thank you for breaking up the paragraph, it makes it much easier to read. Don't be too upset I wrote big paragraphs when I first came too.

You have come to the right place to learn the process you need to accomplish your goals but we have become wary of members who join and post questions they have because their previous information, obviously gained before you came here, has led to problems.

You have likely formed silver chloride which is the white ash you refer to. Had you properly leached the base metals with a nitric, distilled water mixture you would have gold foils, any undissolved stainless steel, and all of your base metals and silver in solution.

Rinsing all of your undissolved with distilled water and collecting it on a filter will leave you with a solution of base metals and silver nitrate. There are many options for recovering the silver but once it is converted to chloride, it has to be reduced. That is covered completely the section on silver.

After you have removed any obvious stainless steel that has been stripped of its gold and pulled out the small gemstones in the movement and any crystal watch faces you can then give your solids a little roast (heat them with a torch until they glow red) and weigh them to determine your acid needs and now dissolve them in aqua regia.

You description is lacking some details, as I have never seen urea raise the pH of aqua regia that high. If you have raised the pH to 12 (although I still do not see how from your description) you will have dropped all of the base metals out of solution and formed a sludge of insoluble metal hydroxides which are mixed in with your silver chlorides and gold. That has been done before and you can find it documented on this forum as well.

So don't throw anything away, store it in a safe place and start reading. You will be able to recover from these mistakes but to avoid them next time it will be best if you get a few principles down first. They are all available here for the small investment of your time spent reading. You can also fill in some of the details missing from your original post, like if you used distilled water or how much urea did you add to how much acid.

Don't be discouraged, like I said you came to the right place and you will get help.

 

[butcher]

Luke,

To save the values from this batch, I would use a large clean electrical bus bar or thick piece of copper metal to cement values from solution, save all undissolved metals and powders.

I would then treat the waste solution, see dealing with waste in the safety section.

Before going forward with lab work, I would spend my time on homework, reading Hokes book and the forum, the time spent in study will be worth more than the gold, you will be losing by dumping metals into aqua regia.

While reading Hoke's book you can do the getting acquainted experiments in her book, these are very useful tool that will help in understanding some important basic reactions and principles.

This is a skill that take quite a bit of understanding, and study from reliable sources, lucky for you you have found a great source. It sounds like you read a little bit of mostly misinformation on the internet, and think it is somewhat simple, at this point I think you need to spend the time learning, gaining a good understanding of the principles of recovery and refining precious metals.

 

[lukeduke077]

I was lead to believe that for the pre leeching nitric and regular H2O would work fine. So for that process I used regular H20. I think we screwed up at this process. As I had should have let this process go on for a much longer period of time. I think I most likely poured the gold material off when filtering. Thus putting the junk into the second batch.

I do think that the second batch did work. The pieces I added of watch cases were clean. No movements or steel just the case backs that were loose. All of the gold appears to be completely removed form them. Some of the watch caps did remain. But they were chewed up from the acid.

I think you for the information on silver chloride. I suspected to see a little bit of that material. However I am seeing a lot of that material based on 8 OZS of GF Scrap. I am under the impression that silver chloride . Can be recovered after the regia process by placing copper coils into the solution.

The PH sample I took was a very dark maroon color. Based on the guide I was provided. I would of registered it as a 12.

Now when we filtered the aqua regia at the end of the night. We used pure distilled water for filtration. When we could not get the proper reactions to occur urea. We then proceeded to use the sodium Metabisulfate. Attempting to drop the gold back out of the solution. There was a reaction which attempted to occur. However as predicted the high Nitric instantly attacked the reaction.

If I have a sludge of insoluble metal hydroxides which are mixed in with my Silver chlorides and gold. What would I need to do to make this solution stable enough to work with again ?
I currently have my solution in a 5 gallon bucket. Would you anticipate that the nitric is still working. Or is this solution sitting idle and not doing anything.

I must admit knowing how acidic my solution is currently. I tend to be a little nervous to proceed to my next step. Until I can somewhat anticipate what I might see next in the process.

I added about 8 teaspoons of Urea to my Regia. Before attempting to drop the solution with Sodium Metabisulfrate.

Any insight on good search terms would be much appreciated.

 

[lukeduke077]

Butches I appreciate the advice

I think you are right . I do need to do some more studying. I have been saving gold fill for 3 years & 6 Months. I have wanted to do this for a very long time. I have been pleading for help locally. I had someone who is a chemist. However P&G has been sending them out of country a lot in the last 6 months. So I finally thought I had the information I needed and took a big leap. Usually gets me in trouble but then I find someone to teach me .

I hope you all will take me under your wings. I really do love playing with the metals. Kind allows me to release some stress from the day to day grind of life.

So how much copper would you suspect . I need to drop into the solution to drop all the contents. I would then follow your waste treatment and dispose of the liquid. Can I then put that powder back in Nitric or Regia and start over again ? After I do some more learning of course.

Also who is hokes & where can I find her book ?

 

[sharkhook]

A good place to start would be here.

The Guided Tour. Follow the links in that thread and you will find everything to get you started. It is a lot to read, but if your truly as interested as you seem to be you will find it very interesting.
http://goldrefiningforum.com/phpBB3/viewtopic.php?f=33&t=796

 

[rucito]

http://goldrefiningforum.com/phpBB3/viewtopic.php?f=54&t=19807

 

[butcher]

Luke you can find Hoke's book here on the forum as a free download, she also has another valuable book on testing metals, I think you will find this book and other information here on the forum a real gold mine.

I think also after you start studying you will begin to see how much there is to this field of study, it is truly a science, and like many scientific fields there is a lot to be learned.

Most of the silver chloride will be powders, very little silver will go into solution in aqua regia (a small bit will).

The copper will cement out values from the solution, How much copper that will dissolve will be determined by how much free acid is left in solution, and how much valuable metals are left in solution, once free acid is used up and the values are cemented no more copper will be oxidized, to complete the process you will want some metal copper left at the end point, this is one reason a thick bar of copper is used.

I doubt from your description you have a pH of 12, my guess is you still have a very acidic solution.

I would save the material, after some time studying you will be learning how to deal with any material you come across. at this point I would not worry about going further with this batch as you can recover the values later, I would concentrate my time on recovering from this mistake, and learning how not to make these kinds of mistakes, and begin the long journey of discovery and learning the art skill and science of recovery and refining of precious metals.

Luke,
Every one here will help you, as you take this journey, and begin to learn this complicated science, we all study and share with each other what we learn, and in sharing what we learn we help other in their study.

Welcome to the forum, If you want a good laugh, try reading my first posts, the paragraph was so long, and my writing skills were terrible, (I had the same problem nobody would want to read it).

 

[lukeduke077]

Butcher I just read hokes whole book . I was taking notes refining my strategy . I now have a much better idea of what I need to do. I understand things so much better 8) . I now have a clear plan to proceed with to get the AU. I have noticed that I keep needing to order more lab supplies. I wonder if my return will be worth the time and money I have spent. This is going to take a couple day to do . I will post my future observations for further education.

 

[kurtak]

Butcher I just read hokes whole book .

Hello lukedukeo77

Good job (on reading Hokes) it if the refiners bible & you will find your self referring back to it often - its a book you study not just read

Between her book (Hokes) & the info you will find here on the forum you will find your self captivated by the art of precious metal recovery & refining

There are many sources of material from which you can recover & refine PMs & this forum if full of such info

This forum is the absolute best source of information in the world on what kind of material has PMs - how to recover them & then how to refine them

Welcome to the forum & may you find the journey rewarding

Kurt

 

[necromancer]

lukeduke077, some other documents that you may find useful.

 

[4metals]

Before you move forward and try cementing on copper you have to be sure what your pH is. If what you said is true and it is over 12 the copper buss bar will not work.

Seemingly little details, like what the pH is, make all of the difference in the world in processing.

By the way, you read that book pretty quick. You first heard about the book at 11:30 last night and by 6:30 this morning you have read (and understood) the book? A lot of coffee and no sleep I guess. That much information doesn't sink in as fast as you seem to think it does. Nor does saying what you think we want to hear.

 

[necromancer]

By the way, you read that book pretty quick. You first heard about the book at 11:30 last night and by 6:30 this morning you have read (and understood) the book?

i was going to say just that, seeing i got a kick in the upper front of my pants just a few days ago i kept my mouth shut.

 

[butcher]

Luke,
You sure are a fast reader.
I still think you are rushing into things, being impatient to get the gold is a good way to miss or lose the gold.
There are many more things to learn, and reading Hokes book does not necessarily mean you understand the chemistry involved in the book or the principles involved, I have been reading that book for years and I still learn new things to help me in recovery and refining.

The information in forum take will take what you have read in Hokes to another level of understanding, between these two sources and other information you can get a very good education in this science, and with the help of other forum members.

You should study more before, you start spending money on lab equipment,and supplies, I have spent very little money stocking my small lab, when I first began I thought I would be needing certain supplies and chemicals, I still have not used in years, I bought some fancy lab glass, it still sits new in boxes (it is too pretty for me to use), when I first started I spent more money than I should have getting scrap materials to recover and refine, I overlooked good sources for precious metals, not having an understanding of where the values are, I lost a lot of gold trying things I did not understand well enough or sometimes had no real clue about, basically I studied for years to build an understanding and my skills, it takes time, knowledge understanding and patience is the key, impatience jumping in and being in a hurry to get the gold before you gain a good understanding leads to loss.

The gold will still be there, you will be able to find it and recover it better, the gold will give you the time you need to spend on learning.
You have gold fever right now, calm down, relax, build your education, that is where you will get that gold.

You have just began the journey, a journey that can last several life times, don't try to jump to the end before you even really begin. you would miss so much of what is really there. sit back and enjoy the ride, you will pick up that gold along the way.

 

[butcher]

necromancer,

I believe GSP was just trying to avoid some of the problems, and tone on the forum, (like the wolf pack mentality with new members...), with his comment the other day. To improve the forum, which I know is also what you wish to do here, to help members of the forum, and also help our new members get started learning.

Nobody kicked you. you are just perceiving, or receiving it wrong.

 

[lukeduke077]

I am not doing anything with the solution. Still reading all the links that you fine folks have supplied me. I am very grateful for all the help on here. I read that whole book last night because the subject matter was so interesting. I will grant you that rereading will be vital. Is there any way to purchase a copy of Hokes book. I looked on ebay and they are all over a $100.00. I take it that she wrote this book circa 1920 to 1940. I know the prices of raw material are not nearly as cheap today.


I think that what we did wrong was the following .
1. We did not steam or boil the extra nitric out of the solution.
2. Outside temperatures were to low to produce desired reaction. Which made both the outside & inside temperature to low to produce proper reaction
3. I also think some patience to allow the reaction to work properly. Would have achieved a mush better result.
4. No rinsing & re washing to place.
5. I should have shotted the pocket watch cases for faster consumption.
6. I did not add the Sulphuric acid to remove the lead out of the solution. ( Thus the white powder I suspect is tin & silver chloride mixed together. )
7. I added Urea & Sodium Metabisulfate.

My main question at present is the following.
With the Urea & Sodium Metabisulfate in the solution.
Is it safe to proceed with steam bathing the Nitric acid out of the solution ?

My initial hypothesis is the following. Going with Chapter 5 Beginners used to much nitric.
1. Replace liquid in a glass vessel.
2. Place in a steam bath.
3. Add a small amount of Sulphuric Acid to precipitate lead out and start to drive off the nitric.
4. Allow solution to cook down to syrup. ( Not letting the syrup burn or harden into the bottle of vessel.
5. Add small amounts of hydrochloric acid to drive off any remaining acid.
6. Let the dish cool then rinse with distilled water.
7. Place material in large vessel and dilute with 3 to 4 times solutions volume of hot water.
8. Let solution stand for a few days to allow silver chloride to settle. ( solution must be perfectly clear before you proceed any further)
9. Filter solution recovering the silver chloride. ( If any lead was present in solution chloride will have lead crystals)
10. Wash Silver Chloride and place in the silver jar
11. Clear solution will contain the gold copper zinc etc
12. In another vessel dissolve Ferrous Sulfate ( green copperas) into to warm water. ( using ratio of 50 Pennyweights of gold to 1 Quart of water & 1LB Green copperas I.E. Ferrous Sulfate.
13. pour solution slowly into gold solution and stir.
14. Allow material to settle overnight. Brown powder should emerge in the bottom of vessel.
15. Gold will not settle if nitric is still present.
16. Keep adding green copperas & water stirring frequently until the gold drops.
17. Now test the solution with Stannous Chloride to make sure no more gold is in the liquid.
18. When no more gold is present in solution filter the liquid off and discard.
19. Rinse gold in vessel and filter off the green copperas.
20. Add hydrochloric acid and boil again to rinse the green copperas powders out of the gold.
21. Repeat then rinse gold thru filter with plenty of hot water.
22. You should be left with a clean pure gold powder.

I looked at solution this evening and it is still active consuming the material in bucket. There were some watch caps down in the bottom. They have all now been completely turned white. I think they will disappear completely tomorrow. There is also a solid paste layer in the bottom of bucket. All my gold that was visible is now dissolved.

Gents I take this serious and have no desire to get hurt.

I ordered a beaker set today . I ordered the plugs for my beakers. I also ordered a spot plate. A couple glass droppers. A pack of glass stirring rods. Some green copperas & potassium Nitrite for cleaning gold in the crucible. I do plan to do the experiments in Hoke's book when the supplies arrive. I also ordered some Stannous Chloride.

As to Hoke's Book . I did stay up all night and read every chapter. I did not find platinum information to be super useful yet. However I am sure it will become very useful in the future. My main focus was rereading chapter 5 and a few others including the silver chapters. I was focusing on learning why the solution turns the colors that it does. I found it very interesting learning what elements cause what effect. I also found the testing solution sections to be very helpful.

Heck the stuff I rinsed and cleaned off. I placed it in a jar and it is still braking down as well.
I know I have a lot to learn yet. But compared to where I was 2 days ago. Seems like I can see into the valley below a little better now.

 

[lukeduke077]

Here is a pretty big question ? When you heat regia to a simmer. How far can those gases travel before they become mostly harmless ? I live in a town and have neighbors fairly close. Are they going to call the law on me because of the smell ? Do you need to live on some fairly open land to this without harressment ?