Sreetips Silver Recovery From Brazing Rod
HTML-код
- Опубликовано: 9 янв 2018
- To contribute: paypal.me/sreetips?locale.x=e...
I extract the pure silver from silver solder brazing rod using the silver chloride conversion with lye and sugar method 
Наука
Наука
I’ve been saving brazing scraps for years. The plant that I worked at use to throw them away. I’ve got 35lbs saved. It’s all 80.15.5. Now I know what to do with it. Thanks sreetips!!!
Use electrowinning to remove the copper and save serious cash on nitric acid.
I use this material all the time at work and have bought 10lbs for cheap awhile back to play with.
For fun and in small quantities, sure nitric.
35lbs….I’d build an electrowinning set up. And the precipitate in the video could be phosphorus??? I know they use some of that in stay silv for a self flux as it goes molten it burns up creating a tiny atmosphere, but when dissolving it could turn into a powder. I have the msd sheets in my cupboard.
Thanks for the info! Great demo of dropping the silver with lye and sugar.
Thanks for making and posting your video's, I enjoy them all
Sreetips thanks for making the videos you make, they are very informational. You are also very good at explaining what you are doing as well as what is happening during the process. Thanks again for quality content without the bull other channels upload.
Mad Scientist, beautiful, thanks for sharing your passion with us.
I love your teaching! Watch you all the time.
Just wanted to take a second to thank you again for your efforts of making these videos! I’ve learned a lot from you as well as others and really appreciate your time in making these for us. I’ve yet to go refine any silver as the nitric is expensive here in Maine. I’m currently searching for a cost effective way to purchase nitric but until then I’ll keep using poor mans. But thanks again! Stay safe
Try dudadiesel.com - but you may have provide a company name and business (no residential) shipping address.
Excellent job sir. I really enjoy your videos as you don't talk to the viewers like we don't know what HCL or a ML is. I will continue following you.
great videos, I really enjoy watching! I would really like to see one on nitric acid production.
Gonna call this one the moon round.. Alot of work but came out good in the end 😄 love the info for your videos
Another great teaching video! Thanks Pete!
Very interesting to see. Don't be surprised that in the evolutions of stock pots you may come up with a new element, lol.
Thank you for the addition of the thermometer!!!. By the way... I love this channel!!!!
Dru, I remembered that reporting the temperature was mentioned by someone. I'll try to include it in all my future videos. It is an important aspect. Thank you for pointing it out.
I very much enjoy these vidoes!
Whodathunk to recover silver from brazing rods? Sreetips, that's who! Excellent video, the yield was unexpectedly low, but you still have some more rod ends and some silver chloride to process from this batch of rods. You pulled it off nicely, sreetips, a guy could save up the silver solder brazing rod bits, and make a nice silver stash from them. At least they wouldn't have to go into the garbage.
I love watching your videos and enjoy your format. Have you considered including occasional text over the footage, displaying the formula/equation for the reaction taking place?
Sweet video. I do hvac and use those exact brazing rod every day. Interesting. Take care friend
Wow, thats some resilient stuff
Pretty good mate. Keep going.
Thanks for sharing your knowledge... Very interesting hobby!
Another excellent video!
Hey sreetips!! I've worked with Harris 15 for most of my life. What you might not have picked up is that silver brazing rods have a significant amount of phosphorous added to act as a wetting agent when the silver/copper alloy begins to flow. You can buy brazing rods with different alloys all the way from 45% down to 0% which is called Phos-copper brazing rod. You just did in reverse what I've wanted to do for years and that is make my own brazing rods. haha
Cool, I seen these at the welding store and decided to try to get the silver out.
Definitely an education.
Apparently with a learning curve! LOL
Great vid!
It appears that you are a bit fascinated by the sugar-cement action. I was intrigued myself when you first did it in the other video.
Lotsa nitric this time! But that brazing rod is pretty tough stuff.
Not a bad yield. You didn't lose the rest of what was anticipated. It just had a change of address. LOL
Thanx again bud!
I was baffled during production, but later, after reading the comments, I realized what had happened to all that nitric acid. Here is what I learned after posting the video and reading the comments;
According to the data sheet for Stay-Silv 15, it contains 15% silver, 5% phosphorous, and 80% copper. This is where all the nitric went and it's the reason that very little silver chloride precipitated out in the first time I added hydrochloric acid. As the silver dissolved out, it came right back out of solution on to the copper, consuming the nitric acid as it went. The copper consumed the nitric, and the silver consumed the nitric, but the silver consumed the most. With the large amount (80%) of metallic copper present, the small amount (15%) of silver would dissolve, cement out, dissolve, cement out, dissolve, cement out, on to the copper, over and over, consuming nitric acid as it (the silver) cycled in and out of solution over and over. this is why understanding the reactivity series of metals is so important to any refiner at any level.
Great video
Those stick blenders are great. I use it to powder my potassium nitrate before mixing it with sugar to make my little rocket motors.
Another great video thanks
Thank you for this video, I've wondered about getting silver out of these rods and silver solder. I have been in coin collecting on an amateur level since about 1974 and I started working in maintenance, commercial and then later industrial electrical also periods of general maintenance and whatever else was necessary to pay the bills as long as it was legal and ethical, sorry just rambling.
You do a super job
thank u for your video about getting valuble ....things like silver...coper...etc from scrap
salim
always wondered how you would do this thanks
Deffinately a great video. I think you explained the process well. I would have liked to see the pieces of copper coated angle iron one last time. I'm curious as to how thick the copper accumulated on the iron, and if it was consistent like electroplating would be.
Great job and thank you!
Excellent vídeo :)
Enjoyed!, Thanks
Again a nice video with nice explanation ( though you can have only copper nitrate and silver nitrate after solving the welding rods in nitric acid)
There is now chlorine to react in that stage of your experiment
I was thinking that a copper sulfate cell would work better and be more cost effective. Then your silver would be in the anode sludge and wouldn't need to be precipitated , just dried and melted and rerun through your silver cell. I love your videos bro !!! I learned why my copper sulfate cell turned green from the info you gave about your waste bucket.
I was using a stainless steel anode basket I made to dissolve the copper away from silver electrical contacts. My basket started to dissolve and I learned just now that was an iron contaminant from the dissolving basket . Thank you sir 😎
Bravo. Try using a plastic anode basket.
@@sreetips I like your silver cell anode basket better .
Thanks for this video, I *think* that I can determine a way to apply this profitably: I work in HVAC and am also a beginner hobby refiner.
I already seperate/cut my clean copper scrap from the soldered joints when cashing it in because of the superior payout on the clean versus soldered.
If I use the silver soldered copper in order to precipitate silver out of nitric (if Im already doing that anyway) then I can seperate the silver from the copper *and* cement the silver out at the same time.
Thanks again.
I agree
You did an amazing job sir! I'd be most interested in learning more. I've purchased probably around 50 pounds of 15% silver soldier and harvest hundreds of pounds of soldered joints.
It will take much nitric acid to dissolve all the metal. Probably more than the silver is worth.
@@sreetips If you are someone with more time than money you can always recover the Nitric acid by distillation.
I subbed the first time I found this site, one of my go to's for great info. I have accumulated about 40 lbs of high quality computer gold from older computers well cleaned. My problem is finding nitric acid in gallon containers where I live in western canada. 👍
Hello. You can use acid peroxide to lift the gold foils off the fiber board. Then dissolve the gold foils in bleach and HCl. Precipitate with SMB or ferrous sulfate. Not one drop of nitric required.
@@sreetips Thanks, I will do that. 👍
Hey Sreetips, Do you ever look back at these and laugh about the difference in knowledge from now and then (this video). Funny how much we learn over the years.
I have, some of the older feel amateurish.
Looked for the various solder mixes. so there can be Zn, Sn and Cd, Si in it! Cd cadmium oh boy....
Probably electrolytic refining would be the way to go. I'm doing it now. You're my teacher so I respect the fact that you took your time to make this video.
I never considered running it through an electrolytic cell. The large amount of copper (80% by weight) would quickly foul the electrolyte. But it could be added a few pieces at a time during normal silver cell operation until it was completely processed. I don't know what the phosphorus would do to the cell.
sreetips your half right. Run it like you are refining copper and not silver. Then the silver will coalesce under the anode as blacks and then you can refine that. Not copper in silver nitrate but cu+4 plating out on a copper plate. Leaving the silver as a byproduct
Got it, but I've no experience refining copper. I get loads of copper to use for refining from yard sales and I buy copper fittings for cheap as well.
Yes! I think I referred to this in a reply to another comment. This link shows the copper electroplating process real well. You end up with pure copper on the cathode and everything else is in the bottom as anode slimes. The anode slimes can then be refined.
ruclips.net/video/cnJeK9CwkiU/видео.html
You did good job, i'm looking for video of IC chips you did befor
I've never had spaghetti take that long to cook.
Because you did not cook your spagetti in Nitric acid. :-)
No
Good job...bro....
Keep goin at it....
:) :) :)
U r great sir i love your videos pls someday shoot ur fumehood how it works and all thank you sir
Ok, I'll do it. I documented the installation with photos including cutting a hole in the roof of my house for the exhaust stack. It can be viewed on the goldrefiningforum.com my user name there is "kadriver"
Also, your ventilation system is a great idea
It's an old Labconco protector fume hood. I'll make a short video showing the whole setup.
Thank you that would be great. I really do appreciate you.
it looked like a shower stall cut down
The interior and exhaust are all made of fiberglass to resist corrosion. But the outer frame is made of steel. I'll make a short video of it and post it soon.
Great videos. You should do a yield/cost comparison between (computer scrap/gold, brazing rods/silver and $20 scratch off cards).
Sorry, I don't have any experience with $20 scratch off cards.
Have you thought of using the old hand crank blender to prevent as much splattering of your solution? Of course it might be difficult to find one, I don't know if the still make and sell them, just curious.
Yessss
Nice
This was another instructive and informative video as i have learned to expect from you. Thanks for your work.
I watched another man process Silver in a You Tube video...not to refine it to market it... but to make something for which he needed Silver...which I cannot remember...and I did not bookmark the video...ouch.
Well after he had precipitated the Silver Oxide from the Silver Chloride solution he just melted the Silver Oxide in order to retrieve his Silver.
He did not bother with adding sugar or Karo Syrup. He claimed that the Oxygen combines with the Gas during his melt....which makes sense when considering an efficient use of fuel.
Silver Oxide is an Oxidant, I believe. And you are releasing energy when adding the Sugar...perhaps heat which can be added to melt when the excess Oxygen is added to the Gas....and heat is released
So what are the downsides, if any, to that process?
I think I may try that...unless you have a reason why that you are not to do that.
Thanks for your forthcoming answer..
I've been told that the silver oxide will melt straight away. But I've never tried it. However, you must remove as much of the sodium hydroxide as possible before melting the silver oxide. Molten sodium hydroxide will attach and melt silica (glass). If some of the lye (sodium hydroxide) is still present in the silver oxide, then it will dissolve the fused silica melt dish and deposit the glass on to your metal. It must then be removed mechanically from the metal.
Is it possible to process this material also by electrolysis? Thank!
I did an experiment with dilute nitric acid...litle different reaktion produces Nitrogenmonoxide intead of Nitrogendioxide.
The Brazing rods contain Silver, Copper and Phosphorus. Since the silver and copper is soluble, I assume the precipitant you were getting in your beaker was the phosphorus. The Phosphorus is used as a flux while soldering HVAC plumbing.
I work commercial hvac i do a ton of brazing i have been saving my butts for a while i cant wait to cash in
Love your videos, would cutting the rods up into smaller pieces help the process? I am not able to get hold of the chemicals you use in some of your videos, so watching your videos that use household chemicals is really interesting.
Smaller pieces create a greater surface area and would be beneficial
With those rods containing 5% phosphorus I'm curious how that would have affected the nitric acid reaction with the copper and silver. Was the copper being pulled by the nitric while the phosphorus reacted to form phosphoric acid and NO2 and then react again with the phosphoric acid to form copper phosphate? Was that the precipitate that was first noticed?
I must confess that I don't know the answers. The precipitate would dissolve upon addition of fresh nitric acid. The copper went into solution, obviously, but I have no idea what happened to the phosphorus.
Thanks again for another fantastic video. Could it have been easier to dissolve if the brazen rods were melted down first? I am not knowledgeable on the subject of welding but that was my first thought.
No, melting would not change the rate that it dissolved. With that much copper in there, the silver, as it dissolved, cemented right back out of solution on to the copper. Then more nitric was consumed to dissolve the silver again, then it would cement out on the copper - over and over using more nitric acid as it went. This will keep happening until all the copper and silver has dissolved completely. I think I was almost there in the video. I may make a supplemental video and process the residual silver from the waste and from the bits that remained in the reaction beaker.
Nice.
Hi sir. Is excellent vídeo
maybe those rods are 10% silver and you got it all .......GOOD Job
Precip is silver nitrate or what ever the other metal is
enjoyed the video, but why didn't you cut the rods so they would be totally submerged from the get go?
Just caught this video and you have probably already figured it out but... Those silver brazing rods are 5% phosphorus. With nitric acid, that will redox to phosphoric acid, which should not effect what you were doing, but that and some miscelaneous impruities and manufacturing slag, were most likely the "unknown precipitate". I'm a little fuzzy on the subject, but silver nitrate (I) with phosphoric acid, i think will create silver orthophosphate. I'm not exactly sure what that reaction would have had done in your mix, but possibly lowering the yield and leaving some yellowish sludge. In a perfect world (by equation) it takes 4.3ml of azeotropic nitric acid (68ish percent) to dissolve 1gram of copper. At 80% copper in the material, that would have required 1567ml of conc. nitric to get the job done (ouch!). Not to mention the H20 need for solubility. Add in the 82.96ml of nitric needed for dissolving the 15% silver (68.37g) at 1.22ml HNO3 per gram of Ag. The nitric need for copper is why whenever I need to inquart, I much prefer silver to keep the refining costs down (Ag is 28% of the cost of processing Cu). So... my opinion is... two things were battling you (1) a ton of nitric required and (2) possibly some interactions with phosphorus. Maybe a high power chemist could enlighten us further.
Nice video sir excellent and what is this sodium hydroxide is LyE please tell me sir
Sodium hydroxide is lye.
All that sweet sweet nitric acid used.
u should also do a time wrap up of the entire process on ur videos to give viewers time frames of each step and how long it takes as a whole would like to see in total how long things like this take to do and how dedicated u are to ur craft
Did you build your fume hood? Also, if one were interested in getting into refining sterling silver, what books would you recommend? Thanks.
I bought the fume hood on eBay and installed it myself. There are few books about silver refining. I learned how to do it on goldrefiningforum.com
At 25:00 looks like you made colloidal silver (the amber liquid)
I suck at chemistry but I am curious if its possible to also recover the copper and other metals in the rod that dissolved into solution?
Getting the copper is easy, just add the copper solution to a container full of iron. The copper will precipitate on the iron as a fine copper powder and fall to the bottom of the container as nearly pure copper metal. The iron goes into solution as the copper comes out of solution. However, if other metals are present that are lower down the list in the reactivity series of metals, then they too will precipitate out with the copper. I'll do a video on the reactivity series of metals. It's so important to understand how it works and is applicable at every level of refining precious metals, as well as non-precious metals.
I am looking forward to seeing that video. Its to bad most chemistry classes in school are all about the textbook and almost nothing to do with real experiments. Watching your videos helps me understand some chemistry and I enjoy it. Maybe one day I'll try to extract the platinum from a whole bunch of spark plug tips I have collected over the years, I think CodysLab did that in one of his videos.
Do you think that you might have your goal of 2.1 troy oz. When you processed the other parts of silver that was unrecovered? I like that you show the waste bucket and beaker with the very little bit of silver in each. I'm very impressed with how good you are at refining the things that you do, it amazes me!!
Thank you Sreetips!!
I stopped too early. there wasn't much more metals to dissolve.
@@sreetips Thank you!!
I knew there was silver to be had in solder :) Of course it's not just any kind of solder you used in this case... but I'm sure other kinds of solder contain at the very least traces of silver as well.
That being said, were you aware that some older lightning rods contain platinum or silver as well? Be careful though, some lightning rods from before WW II also contain slight amounts of radioactive radium or uranium.
People thought, back then, the radioactive material would ionize the air around it making lightning flow easier; which, all being said and done is a bit weird, since you certainly don't want to attract even MORE lightning.
Thanks for the video and taking me up on my suggestion about the solder :)
Great video
So your the one who suggested it, thank you for the idea!
I'll keep my eyes open for a lightning rod. That would make a good video.
It is still an honor to benefit from your sacrifice in the name of education, thank you again. Would I be correct to speculate the cost of the nitric would negate the recovery on a couple 2lb blooms that are 28% silver according to a spectral analysis?
That would be an accurate conclusion Scott. There is just too much copper in that alloy to make it profitable. If nitric acid was cheap enough, and you came across a large quantity of the silver brazing rod, then it might be worth looking at. Especially when silver gets up around $100 per troy ounce, and it will, when all these financial bubbles start to pop.
Thanks for the reply. I too am afraid that when the Polytetrafluoroethylene wears off the Teflon Don, the markets may close down like a Dutch tulip on a rainy night.
@@scottlund4562 Don't knock our tulips!
I work now ...see you my friend..
Is great you channel..thankz..is very interesting...very good
I'm going to suggest you convert the silver chloride to silver metal by drying it, add 1.5 x molar sodium carbonaste< and just melt in graphite crucible. The carbonate/chloride xixture melts at about 800°C and serves very weLL as a flux. No need to make things all sticky with borax. Just melt and pour beautiful metallic silver. Nickel does not interfere, nor does tin oxide. Easy peasy, no need to reduce before melting. Chemical reduction is not only unnecessary but vastly complicates the mechanics. My technique is dissolve, then prepip as chloride, add 1.5x molar amount of anhydrous sodium carbonate, dump in a crucible and melt. then pour off in graphite bar mold.
Harold_V on the GRF said he tried this method with good results. He said that the crucible must not be over-filled with the chloride. I think he recommended no more than 1/4 full of the dried silver chloride. Because it will boil over with the carbonate and create a big mess in the furnace. I prefer the wet chemical process myself.
If you have braze wire that has been melted down into globs, ours is bAG 24 so 50% silver if you made it into pellets would you be able to use the silver cell to extract more silver than using the dilute nitric acid solution?
Chris, I only use 99% pure silver to run through my silver cell. You could run 90% or sterling silver through it. But with that much copper the cell electrolyte would quickly become saturated with copper. After about 60 grams per liter of dissolved copper in the electrolyte it (copper) will begin to plate out with the pure silver and contaminate the crystal. If it were me, I wouldn't run 50% silver in my silver cell. I'd extract the silver from the brazing material globs first, then run it through the cell, if it were me. In refining, taking short cuts usually ends up costing, time and money.
I have silver chloride black in colour but I can’t recover full silver from it. Plzz help me
Light Blue precipitate is likely tin (IV) oxide, SnO2. Tin is often added to brazing alloys to reduce their flow point and assiust in wetting copper. ASlso be aware that many copper based brazing alloys contain phosphorus, mostly present as copper phosphide.
This brazing material had phosphorous listed on the label.
You might be having issues with the silicon or the bronze. I have probably 10 lbs of 65% high purity rod like that. I didn't know if it was worth messing around with.
I had some Galena which I crushed up in a pest mortis and added to a beaker with diluted nitric acid then ran it through a filter then added hydrochloric acid to drop out the silver chloride. And it look like cottage cheese but my question is would lead drop out of the solution
If you have lead in solution, then you can precipitate the lead by adding concentrated sulfuric acid. It will react with the lead and form lead sulfate. It can then be filtered out completely. The resulting filtrate will be free of lead after you filter out the lead sulfate. This is the reason that I always add a few drops to my gold solutions before I filter them. Any lead that may have made it into the gold gets converted to lead sulfate. I do it even if I don't think that lead is present. It hurts nothing and guarantees that my gold will be free of any lead contamination.
Actually when I was like 14 years old, I grabbed one of the rolls of silver solder and melted it down into like a pluck and then had my mother look at it. Well as it turned out, I told my mother that I found the metal. So she had someone look at it, and sure enough, it was silver and the person purchased the pluck from me giving me $10.00.
I used 40% Nitric ..that's about 8 mol of Nitric per liter... so I needed (fictionally) half a liter of Nitric = 4 mol of HNO3 to dissolve 0.5 ( 3 x 108) = 162 grams of Silver. You need that for every metal and also need to take in account what the solubility is. You can also see that in diluted nitric with every 3 mol of Silver 2 mol = 36 grams of water is formed.
Hello
please make an experiment for us.... if can we recover silver from plated stuff or from silver scrap ... with vinegar and H2o2 ...! thank u very much.
Yes, I've gotten requests for that in the past. I'll check into it.
Angle iron to put in your waste bucket is quite expensive. I would suggest looking around local train tracks for discarded railroad spikes and rail plates. They are free. I use them in my waste bucket.
I agree, those three pieces cost me about ten bucks. I've just never taken the time to go out and find some scrap iron. I've been like that as far back as I can remember, convenience over frugality. Probably why I am broke today!
How about using scrap auto brake discs. Big surface area and plenty around.
Hi my friend...
Is excellent your vídeo..
Congratulations for you channel..
You have good day...
Yes very good...silver..
Hey did u ever figure out what the white precipitate from the remaining brazing rods in reaction flask was.
That's Silver Nitrate including the stick looking things at 16:50. The Silver had turned to the silver nitrate while still intact as a rod.
What if you disolve the brazing rods in hydrochloric acid and hydrogen peroxide and silver should deposit on the bottom??
Hydrochloric acid would react with the silver and form a passive layer of silver chloride. Once encrusted, it protects the metal underneath from any further corrosive action from the acid.
What happened to the 5% nickel? Awesome video, I’ve been trying to learn how to do this for years
Nickel is considered waste
For Copper in dilute nitric : 3Cu + 8 HNO3 _> 3Cu(HNO3)2 + 4H20 + 2NO = 3 (63,5) + 8(63) -> 3(188) + 4(18) + 2(30) so I need 1 liter = 8 mol nitric to dissolve 190 grams of Copper..with that reaktion also 72 grams of water is produced. But as we have seen in the Soluability tables Copper nitrate dissolves much less in aqueous solution than SilverNitrate....I put some effort in it Mr. Sreetips...I hope you can digest this.
Yes, you have a firm grasp on the chemistry. I know very little about the chemistry. I just go by the seat of my pants relying on my experience to pull me through. Thank you for that analysis.
Great video and very informative - I always wonder why Americans pronounce “solder” as “sodder” 😉
Because that's the PROPER way! Just because you are from over there does NOT mean you are right all the time! BAH! The "L" is silent!
Brett Davies the words etymology started out from Latin as from the word “solidus” but then was transformed into old French as “souder” then “soudure” and then “solder” in Middle English.
So, pronouncing without the L is the more modern and correct pronunciation and including the L would be a much more ancient and archaic pronunciation based off of the Latin.
At what point did you convert the silver nitrate to silver chloride?
Ken
I have not watched the video so I'm not dead certain, but it should have been at the point that I added hydrochloric acid. Silver chloride forms instantly upon contact with HCl.
If you have a problem with some gold mixed up in silver solider can you do this same process and leave gold behind
Yes
Looks like the moons surface on that one side
Thanks what I said
Did you figure out what the sediment was during the nitric acid stage? I've been dissolving whole circuit boards in nitric and have been dealing with mystery sediment the whole time. I don't know if it's good stuff or bad stuff... but it is a tan color and it settles fast, leaving a forest green liquid that looks just like stuff you had in a palladium video. I really don't suspect mine is due to large amounts of palladium though.
Get some stannous chloride. Lean how to identify metals in solution
@@sreetips Thanks for the keywords to search. One of the videos that pops up is from you. I watched it and leaned some things, but in it, you said that you didn't know [the answer to my question]. You could have just answered with that, but then I wouldn't have gone and leaned from the combination of informative clips.
What do you do with the waste once you cement everything out of it. How do you dispose of it?
The waste has to be filtered and rinsed to remove the liquid, then it's dried out and thrown away. It's pretty much useless because it is contaminated with other metals that cement out on to the iron with the copper. Most places that recycle base metals don't even want it.
Why not filter it out vs. siphoning? Thank you. Really enjoy your videos.
I siphon the clear liquid to avoid disturbing the material that has settled.
Right, but aren't you wanting to get all the acid out by rinsing and stirring? Wouldn't filtering get it more of it out faster? Thanks.
Just wondering, are you able to recover and melt the copper you get off your iron or do you not bother with it?
I throw it in the trash. Too much cheap copper out there to both with the copper from my waste bucket.
I suspected as much.
Thank you for the information and taking the time to reply.
3(108) + 4 (63) -> 3 (170) + 2(18) + 30 grams...this is molar mass...just the mass numbers added of the molecules.
Sir plz meak a video for silver recovery from ct scan & mri film plz
I've got a video on silver recovery from X-ray film. Should be the same process.
I would love to see you extract palladium from automobile headlight reflectors. Also, why is nitric acid so expensive? According to Alibaba it costs less than $400 per metric ton in China.
I found a company that will sell a keg (pour boy) of 14 gallons of nitric acid for about $400 in Alabama. But they also charge a refundable $600 deposit for the stainless steel keg. Check goldrefiningforum.com for more sources of nitric acid. Those guys know their stuff.
Do you think your company will ship it to me in Ak? Locally it costs me $55 for 500ccs. I have had some shipped for much less