Problem dropping gold

[Charles Connor]

I have already seen the coffee maker being used as a heat source and some people use to put some sand on the plate, will give it a try, because once I used an electric stove with an aluminum piece so the heat weren't that direct and my 2L beaker broke, so I don't want that to happen.
Göran and Butcher that's a new level on de-NOx-ing gentleman!

 

[AtoMIKu235]

After boiling and using Urea and then trying to drop with SMB, precipitate dissolved, , , Doooooooh I think i have Problems with to much SMB and need a little more De-NOX , , , Managed to drop gold by adding very small amounts of sodium Hydroxide, gold likes to drop first, but if you add to much the other metals will follow , , , , test with SnCl untill no gold, preciptate is unusually fine, it will settle in 3 hours, check for tiny metalic gold particles on the surface, spray them down , , ,Mix powder with HCL to remove base metal contaminants , , , have a small problem of NaOH reducing AuCL to metalic gold which forms on side of beaker , , , , , I think this is a good new method to recover failed refining , , , have anyone got any idea,s on this subject , , ,

Micky B

 

[butcher]

My idea is not to use the hydroxide to lower the pH, gold will precipitate just fine from acidic solutions.
Why add something that will contaminate the gold you are trying to refine?
Our purpose is to leave base metals behind not drag them along with the gold.

Spending a little time reading the forum and you will find a lot of information on this topic.

 

[AtoMIKu235]

The fact is my NaOH method works, there is no contaminants as far as i can see, and after using Borax and sodium carbonate flux my gold is relativly pure, and tests ok with NHO3 , , , Better than throwing it in the waste tank

Mickey B

 

[butcher]

Mickey,
No offense but I do not believe your methods are working (or at least as well as you believe them to be working).
yes you may be able to recover some of your gold, but my guess is you are losing gold and making it more difficult than it has to be, I believe from reading your posts (Boiling, use of urea, NaOH, and using NHO3 for nitric acid...) you can benefit from more study to learn better methods of recovery and refining these precious metals.

If you do not see where things are broken it would be hard to fix them.

 

[joubjonn]

Sulfamic, buy some. It works every time. Or just don't use too much nitric in the first place which was not my method In the beginning but now that I'm getting better at this and seeing an actual "pipe" when my buttons cool I know I'm doing it right. Which would not be possible without the wisdoms of this forum, from folks like Butcher!

 

[Anonymous]

Mickey what do you define as "relatively pure?" Can you give me and idea of where you mean with regards to this purity?

Jon

 

[Anonymous]

Sulfamic, buy some. It works every time. Or just don't use too much nitric in the first place which was not my method In the beginning but now that I'm getting better at this and seeing an actual "pipe" when my buttons cool I know I'm doing it right. Which would not be possible without the wisdoms of this forum, from folks like Butcher!

If you clean your gold properly mate you'll always get a pipe regardless of the accuracy of your drop.

 

[Chirou]

Hi guys i heard that's if i run out of other chemicsls i can denox with smb. But how to calculate IT than? Add untill no morę fizzing or what? Smb od really chrap here and well i got urea but i decided i dont want to use IT after reading this toppic. And i'm on middle of process. Into one batch i already added urea And its shame to admit but due to some spends i cant afford sulfamic acid this Monty Its not that's expencive but the cost is half what i got left lets sat Igor 42 euro to end of month and it will cost 25 plus delivery ... But currency here od different xd. And Igor to struggle roll end of month im doing all recovery outside and its getting colder. Please advice me and help guys^^

 

[butcher]

I would add a gold button and heat solution.

 

[FrugalRefiner]

As butcher said, you can add more gold to use the excess nitric.

Or you can heat your solution gently and evaporate it down till it's like syrup, then add a bit of HCl. You may need to do it a few times.

Or you can add a bar of clean copper to the solution to use the excess nitric and cement the gold out of solution.

When you add too much urea or SMB, it starts to create other problems. In the future, the best procedure is to add as much HCl as you expect to need, then add the nitric in small amounts at a time so you use just enough to dissolve the gold. Then you don't have to deNO_x.

Dave

 

[Chirou]

Don't have any gold yet. These are my first batches. Into one i added urea and well i think it's bad cause all truned brownish-black and i noticed some clear/white crystals and as far i read this is also urea's doing and in second one it looks like theres a little bit of gold residue but the color of solution is still greenish brown. And i'm not sure if i messed up here adding urea earlier or in some other way
first batch are PCBS in big bucket and it's rather hard to heat it now it is around 6liters af solution in total. (processed like 3 full PCBS[clear without any components or tin, maybe on one or two a little bit of tin] buckets in it). And well now i'm broke at this moment and a bit confused. I'm searching for some cheap sulfamic acid but well its still almost 3/4 of what i got till the next paycheck.
And i would like to procees these gold solutions as soon as possible cause cold weather is coming. And i;m doing everything outside 8km from home with no electricity there.

 

[butcher]

Chirou,
I would like to hear more details of how the gold was put into solution, more about the source materials, the more details you explain will give a better picture of what you are dealing with.

Were there metals left undissolved, or were whole circuit boards involved...

Take FrugalRefiner's third advice and add a clean bar of copper to cement values from the acidic solution. from your short description of your solution, you have base metals in solution, any gold will convert to metal.

 

[Chirou]

Well first batch is from gold plated pins i put them into nitric acid, let them sit in 3 jars (i got a lot of pins).
2 of 3 went great o got all copper disolved and was left with only gold foils(of course with some little leftover copper). Third one went bad there was some iron containing pins i didn't notticed and i got Fe2O3 inside with foils. I dissolved all collected foils and one batch with a little bit of Fe2O3 in AR. And got pretty umm dark yellow solution a littlebit green i can say. I used urea well my bad. And added SMB. It looks liek gold has precipitated cause i saw brown residue on bottom, but still solution remained almost the same color, got lik greenish brown now and it sits 2nd day. I didn't had enought time to filter it today.

Second batch is clear PCBS in plastic bucket i put them whole inside (i got a lot of goldplated pcbs and connectors etc from place where i work for free). I put whole bucket and added a bit of water than 35% HCl and 65% HNO3 and i think i added too much cause i was able to process almost 3 buckets of pcbs in this batch. Everything was going great beauty green colour. And well i added urea untill no more fizzing, waited some time. And than added SMB diluted in water pretty much nothing happened i waited some time and added one little spoon of powdered SMB thinking (if i drop some copper i will rinse it multiple times with water and than rinse with HNO3 to get ridof copper). Solution turned brown so i left it be thinking that its going well but when i checked it after around i'm not sure 1 hour i saw it became more black than brown, and after moving a bucket a little i noticed a little crystals stuck to side of bucket clear maybe a little white (hard to say cause bucket is white). I did some research on out forum and found that i messed up by using urea.... and that these crystals are probably urea nitrate (i hope not) or Copper Chloride. (both are soluble in water) but now i'm not sure if my gold powder stayed in solution or is trapped under the cristals. I got one of my very first batches like test batch and there i got the same cristals in jar with black-brown powder trapped under but here i can't see it. And i got confused and i don't want to lose any gold. I got a little copper slab from radiator maybe it will be od use. But still please advice me on how to not mess up anything more ^^ i'm not expecting huge ammounts of gold but still it's waste to pour it out.

Now i know not to use urea.... I need to buy sulphamic acid but well i probably need to wait till next month. Or find a way to earn something on side. I'm neewbie lets call me refiner. And i just want to make little gold ingot from all that i can get where i work during my life and later pass it to my children (when i get some XD ).

Thank yoy for your time ^^.

 

[Chirou]

Oh sorry i forgot to mention that in PCB's batch when all metals were dissolver i removed pcb's and filtered solution from leftover little pieces of pcb's etc. Than placed it in cleat bucket and started with urea and SMB.

Update.
As i think about it now i can heat up solution but in portions. I mean i can't heat whole bucket now but i can take my old grill fill it with with sand i will get from near lets call it excavation. place it under a little fire and put small jar onto it it should work like crock pot (i think i wrote it wrong) like one Cody from Cody's lab uses.

Of course i'm no specialist. I kinda want to stay and try gold recovery and never give up cause this all gold recovery idea, forum, movies on yt etc got me out of depression and gave me a little goal little something what i can do. ^^ ill strach picture od Cooper slab i got but i Think i will use something a little smaller easier hang inside.

 

[butcher]

As long as you have saved everything you still have your gold, adding the copper will cement any valuable metals from solution, the Oxidation of the copper metal atoms will give up their electrons to any gold ions in solution, as the gold ions gain electrons (reduction) they become metal atoms which join to become a powder heavy enough to precipitate from solution.

The cemented gold will be black (still impure gold), which may be mixed with other insoluble salts.
The solution should be acidic (yours probably has quite a bit of free acid), stirring will help, as each gold ion in solution must come into contact with the pure copper atom for the electrons transfer, some gold may stick to the copper which can be brushed off with a toothbrush if needed.

Store your gold after decanting, we can discuss washing and further steps in more detail later, for now, study up on proper and safe disposal of the toxic waste you have created thus far, ask any questions you do not understand after reading more on the process.

If you are truly ready to learn to recover valuable metals and learn to refine them you have found the place.

I suggest forgetting what you think you know about it, and let us get you back on the right track of learning how to...

 

[Chirou]

Ok thank you very much.
Problem with waste is noone here really takes care of it but as far as i read if i cement out copper with iron and than make the solution basic i can bassicaly pour it down a toilet. I Have to cement out copper cause it's toxic in solution. Of course correct me if i'm wrong cause it's very possible.

I'm working 14-22 now so i don't have time to go and check on my gold but i got few nice pieces of copper from work and i can use it i think i will even get more tomorrow. I'll get friday off and go to donate blood, and than go to place where my gold solutions are and start cementing it out. I got really a lot of gold containing scraps PCBS etc from work so gold recovery its a great way for me to kill free timem have fun and create some small button or maybe some ingot over years.

Thank you very much for your help. I will post any progress in this toppic ^^.

If my solution would be not acidic enought i understand i will need to add some acid. And as i deduct from copper solution should turn more blue when gold will be cemented. XD

 

[butcher]

After cementing out the copper with iron, Iron will not replace all metals from solution.
https://en.wikipedia.org/wiki/Reactivity_series

we need to bring the pH up above a neutral solution, into the basic side, as you can see from the chart below not all metals will precipitate, or have a lower solubility at the same pH, some metals as you can see from the chart are amphoteric, and can be soluble in acidic condition, then lower in solubility as you raise the pH, and as the solution gets further basic will dissolve back into solution, some of the major amphoteric metals like chromium, zinc, and lead you can see from the charts graph below.




As I said earlier forget what you think you know and study the material available to truly gain an understanding, I would not dump anything down a toilet, hopefully, the men living upriver from you are not dumping their waste down their toilets, what people flush up the river, is the water down river people drink from.

Study this:
http://goldrefiningforum.com/phpBB3/viewtopic.php?f=47&t=1300
There is much more in our safety section.
Understanding how to deal with waste has many of the principle basics needed to understand recovery and refining of precious metals, without these principles you would not only struggle in your understanding but will put yourself and everyone around you in danger.

 

[Chirou]

Ok i've been to place where i keep all my gold etc. I put some copper pieces (i think i can call it rods) into solution Well i didn't noticed to much of change after 4h only that cooper got lighter so i guess that it started to get into solution. I stirred it few times. Saturday i will go and check on it and continue process. And i filtered one jar got a little bit of gold dust on the bottom. But solution remained green so i put copper into it as well.

I'll report Saturday or Sunday. And now i'm starting to study how to deal with wastes as you said ^^.
Thank you very much.

 

[butcher]

The copper is being oxidized giving up its electrons, the copper atoms will go into solution as ions (atoms missing electrons), as copper atom gives up its electrons to the acid the acid is reduced (gain of electrons), copper ions color the solution, the ions metals which are less reactive than copper in the electromotive series of metals will gain electrons from the copper atoms (the copper being oxidized, will reduce these precious metal ions to precious metal atoms with a full shell of electrons, leaving copper and the metals above copper (see the electromotive series) in solutions as ions, or ionic salts of the metals (cations), and the ionic salt of the acids used (anions), leaving you with your values, a toxic solution of many of the very dangerous heavy metals in solution.

Note, Tin in solution complicates matters, the tin will form gold colloids, these colloids are already reduced to metals in solution, so copper cannot reduce them as they already have all of their electrons in the metals atom, we cannot test for them with stannous chloride or ferrous sulfate as neither reducing agent can reduce the already reduced gold, we cannot precipitate them from solution as they gain charges that repel each other the clusters of reduced gold cannot gain a large enough size or mass of gold atoms in the cluster to be seen or to overcome gravity in this solution of repelling clusters of gold colloids.
It is difficult to break the colloidal bonds to recover this gold, which can be a good way to lose your gold and not even know it.
Tin should not be dissolved with tin or solder from circuit boards.