First Timer Looking to Learn

Hello forum,
Wish I would have joined earlier, I have been in the scrap biz for many years now (ferrous and non-ferrous), but you have to realize, most of the people you see or meet at the scrap yards have no clue about gold recovery or refining....so what I know thus far is from the internet before finding this forum...I always had sold my computers to the local scrap yard for between 25- 35 cents per pound until one day why I was on youtube and seen my first Aqua Regia precipitation.......It was like bells went off in my head, thinking about the years of E-scrap I had been selling for close to nothing....I knew there was gold and silver in computer parts but had no clue how I could extract them..........As I began to do my research I found out about the AP process and it seemed easy and cheap enough so instead of sell my E-scrap I began to stockpile it........Eager to get something outta what I would have normally sold I began the AP process on a small amount of what I had as a test run or experiment ......I started with three mason jars 1/4 full . One of broken off fingers , one of misc. cpu's , and one of pins...After a few days, as the gold was stripped I filtered the solutions . Then washed repeatedly with HCI and then water. What was left covered the bottom of a baby food jar .....I looks pretty clean except a few tiny fibers ....Now that I've been doing more reading on the subject(Hoke's book and this forum) I was thinking of using AR to refine what I have done so far. Has anyone been down this road besides me, or has anyone tried this process....I'm trying to be super cheap because I don't make alot of money scarpping metals to begin with......any help would be appreciated thank you in advance ...

Read C.M. Hoke's book, Refining Precious Metal Wastes from front to back....twice. Do the familiarization exercises she she instructs. Read the MSDS sheets for every chemical you will work with before hand. You can find a download for the book on this website if you use the search bar. Welcome!

thank you for your reply....Hoke's book is very informative, I haven't finished it yet...even though it seems kinda outdated.....there was no mention of Urea or SMB thus far but my guess is that those are more modern technics, instead of evapiration to drive off nitric acid Urea is used, and there were several technics to precipitate SMB wasn't discussed......but I did get a idea I'd like to try in future experiments, I'd like to try precipitation with a HCI in gas form using the reation to alumium to create the gas, has anyone tried this yet? I've seen this work before but not with AR.....For right now till I'm completely used to the tried and true I will stick to what definally works...

Nope those techniques in Hokes are not out dated evaporation is still very useful, urea is only good for fertilizer, and SMB in acid is only a way to generate SO2 Gas.

My opinion put the urea in your grass you do not need it in refining, it can be dangerous, cause you to loose platinum group metals, only adds more trash to the mix, urea will not destroy HNO3, do not believe me, try it in a test tube, add some to some urea to some nitric acid and see if it will still dissolve copper, it will.

Hoke methods are just as valuable today as they were back then.

Although here on the forum you can learn a few new tweaks or tricks, like when making aqua regia, do mot make it, or mix it up, but measure out ingredients separately, and only add the minimum of acid needed in small proportions, this helps lower the use of HNO3 and the need for much evaporation, a trick Of GSP's.

Or Harold's trick of adding a gold button to use up excess HNO3 heating solution, or a version of that not dissolving all of the gold leaving a little for next run, with heating leaving some gold behind to insure nitric acid in solution is consumed.

And sulfamic acid which can take nitric acid and make sulfuric acid.

In my mind nothing in Hokes book is old fashioned, but is is methods proven to work from centuries of trial and error, much of what she teaches can be thousands of years old, and some relatively recent, I do not think too much has been changed in refining form her day to ours, maybe a few little tricks, but basically the principles and theory is the same.

Without learning Hokes you would struggle to learn to be able to do what we do, it would not matter how many new tricks you learned, but with Hoke's you really would not have to learn any of the modern tricks because following here advice would work just as well today, as it did 100 or thousands of years ago, the trick then just help you do what she teaches a little easier.

If you cannot tell you hurt my feelings when you called C.M. Hoke's old fashioned, Heck she was hundreds of years ahead before her time.
That puts Hokes book and her methods, up to date, and one of the best and most modern books there is for refining in my opinion, and I have never had a humble opinion.

Scrap happy, good to have you on the forum. Also good to see you are willing to take the initiative to start reading Hoke. As long as you pay attention to the people on the forum, you will not be led astray.

Hoke's teachings are almost all right on the money. At one point she tells you to throw gasoline on a fire. Bad idea,but that might be how they did things in her time.

Make sure you read all the saftey precautions and don't take shortcuts there. Get the proper safety equipment and wear the proper clothing when working with the dangerous chemicals you will encounter.

Butcher, right on target as usual.

Butcher sorry to offended you, not my intent! I agree Hoke's was ahead of her time. And any and all info is extrenely useful to me.So its your opinion that evaporation is a better way then Urea ? I don't wanna get confussed, being new to all this, evaporation isn't a problem for me....I just wanna get a solid technic I can use on the regular that will refine my work...and keep my cost low...With so much misinformation out there.....Hoke's is a great starting point for me.....But I have to use chemicals that are available to me and I guess learn by trial and error .....The truth is I can't afford many errors at this point.....In her book she talks about Green Copperas(Ferrous sulphate)for precipitation, this is something I've never heard of before. And although I'm no chemist I'm farily good at reading something and putting it in practice.. What would your suggestion be for a precipitant after evaporation or should I try to follow Hoke to a T ??Thank you for the info you have already shared and thank you in advance for any more info you can give to me...My current situation was discussed in my first post, I have about 7 grams of already AP'd foils but there small fibers in the substrate... I was thinking that if I used AR i would be able to remove them and purify at the same time...Maybe at best for me and any other newbies you could post a addendum to Hoke's process, with those tweaks and tricks ...I'm not trying to be pushy, I'm just looking for a sound method, so I don't screw everything up, fresh out the gate, so any advice would be appreciated !!!

Scrap Happy welcome to the forum.
The guys are giving good advice as I'd expect and I must say that Hoke really is the book to read and study, it gives you all the background knowledge your going to need if you intend to learn to refine from scratch, and yes it's old but as Butcher said there's very little new in refining or chemistry.
With reference to your question about using AR I'd suggest a halt in your processing, AR has its place in refining and a very important one but there are other methods and in some cases better ones and I believe this could be the case here. Try using the search function and look up the chlorox method, don't just skim over it but study it until you know it inside out and understand the dangers involved aswell as the expected reactions and the procedures to refine your gold.
One more note, please read and study the safety section carefully so your fully aware of all the dangers involved in any processing using chemicals some of these are extremely toxic and dangerous.
Good luck and happy reading.

Thanks Nick, I am researching the chlorox method now and I will continue to read Hoke's books...seems fairly easy, but like you said I'd like to know the process in and out before attempting it . There is just to much false or half truth info on the web...Is there any mention of AP or HCI/Ci in hoke's book if so can you pass on the page numbers for me .....Thanks to everyone helping me get started

Scrap Happy,
You didn't upset me;
It takes a little bit more than that to ruffle my feathers
Hokes did not work with electronic scrap, so I guess there are some things not in Her book, but the most important thing is there, How why and when, and her book teaches all of the principles, gives you the understanding and knowledge to deal with any situation, she does not teach every method of recovery, even for the ore of her day, she was mainly teaching chemistry of recovery and refining to jewelers and refiners, but she taught chemistry without going into detail of the chemistry, she taught principles that could be used in recovery of precious metals in any field of work, these principles apply even to mining ore, or mining electronic scrap, and recovery of values, then she taught the principles of refining of precious metals, she did not teach every technique in every field, but she taught techniques that can be used in any field, she did not teach using every different kind of acid or recovery or refining method of here day, before her day or after her day, but she did teach the principles on would need to understand to be success when working with any of these other methods, you could follow her advice word for word and would be successful, and if you learn the principles of what it is she is teaching (seeing the bigger picture) you to will learn the principles needed to recover and refine any material, You would also learn to make your own decisions of how a material could be refined, and you could make a decision with which method would work better, you would understand how not to get yourself in a bind and make a big mess, and if you did make a mess, you would understand how to get yourself out of the mess with what you learn from her book, not with just the type of materials she is teaching or not just the materials she is working with, or the chemicals she is working with, understanding her book will teach you how to recover and refine precious metals, and become successful.

Copperas is just an old name for ferrous sulfate FeSO4, basically iron dissolved in 10% sulfuric acid H2SO4, it works great to precipitate gold, and most likely has been used to precipitate more gold than SMB could even dream of, copperas, ferrous sulfate is easy to make, I have made several post describing how I make it.

Aqua regia is a great tool, but it is like a very large sledge hammer, some time you only need small tack hammer to get a job done, and the sledge hammer may make the job harder to do, especially when a tack hammer is easier to work with, and will do a better job for the type of material you are working with, aqua regia take a lot more understanding of how to deal with it properly, the internet makes it out to be so simple, it is not, there are many small important details that you need to understand to be able to use it without losing your gold, like knowing how to heat it and concentrate it without causing a boil-over and losing all your gold and hard work in the dirt, there are several small but very important details with its use that is very hard for a beginner to learn, and several details you will learn on the forum that will add to the best way to use this sledge hammer properly.

HCl/NaClO (bleach) sodium hypochlorite, is much easier to deal with, it works great for gold foils or gold powders, the oxidizer NaClO is much easier to deal with, this tack hammer, is one that can get the job done and for certain materials like for fine gold powders or flakes, can do the job just as well as aqua regia, and is easier to do successfully.

recovery and refining there is so much to learn, at first you may become over whelmed, there are so many techniques, and different methods, so very much to learn, so much to it, so many very small details that are so important to taking a material from beginning to ending, and you may have to learn many procedures, each with their own small important details, that one missed step could mean failure, success or setbacks causing many problems, studying Hokes and the forum, is were you will learn the details, and steps.

Here is my suggestion, forget about recovering gold and refining it, do not jump off the cliff head first, collect material, spend time learning how to mechanically separate it and preparing it for a recovery later, study the forum of how to find this material, and how much to pay for scrap (electronic scrap a good price is free), Higher grade scrap like karat gold or sterling you can learn were to find good deals how to test and buy it.

Read Hokes Book all the way through, then go back through it again reading, this time doing the getting acquainted experiments, which teach you the principles, and give you the hands on skills to understand recovery and refining, study the forum.
Start with memory fingers, learn each step, how to prepare them. How to recover the gold, then how to refine the gold, this material is easier than almost all other materials to work with, use this material with what you learn from Hokes and doing her experiments.

Don't worry about getting gold at first, collect and let it pile up until you are ready and have a good understanding, your gold will not be lost if you do not dive off the cliff head first and lose it, study safety and dealing with waste read these in the safety section and also study this on the web.

In the general chat section take the guided tour of the forum, see welcome to members, and read the general reactions list, the guided tour will guide you through many of the process you will be using later.

And do not skip reading getting your gold pure and shinning (in the help needed section), here Harold show us his gold washing technique, that will make our gold shine

Welcome to the forum, the best place in the world to learn the art of recovery and refining precious metals, here you will meet some great people, and get an education in the chemistry of metals that I doubt you could get from any college in the world, you will learn the art, and skills, that has been hidden from man from the beginning of time, passed down as secrets, or not revealed, because of its value.

I think you have just found scrap happy heaven. :lol:
Just take it easy, spend a little time checking it all out, before you dive off that cliff.
And you will be swimming in the golden glow in no time.

Hi happy scrapper.
Yes I've been down that road. reading your post reminded me of when I first came to this forum. I was scared, unsure of what I was doing, I was collecting foils and Geo,Butcher and many others were teaching me as I studied. I ended up with my first button, 19grams. I was like discovering girls for the first time! ha ha!
You can read my early experience with ap and fingers "recovering my foils after ap" in the need help section. it contains alot of advice I received from the members here.
You need to study the safety section and how to deal with wastes eventually.
Good Luck and welcome to our forum! artart47

Sorry these are work around methods largely developed here on the forum as many members can't source nitric and cyanide and in many ways probably for the best, the good lady Ms.Hoke didn't have these problem but her teachings are still goid to get that grounding in refining and in the terminology we use.

butcher said:

urea will not destroy HNO3

Click to expand...

Butcher,

Are you quite certain of this? I thought that urea and nitric acid react to form urea nitrate.

I have used it many times to kill the excess nitric acid in my silver nitrate solution, though less frequently of late.

I use less nitric acid than I need to dissolve a given amount of sterling, so that there is usually some undissolved silver left over - this ensures that the nitric acid gets used completely when i digest my scrap silver.

But every now & then I add too much nitric acid to the tailings (the pieces left over in the reaction vessel) and end up with excess nitric acid in my silver nitrate solution.

I can always tell when I've added too much acid because after adding the copper to cement the silver I start to get lots of bubbles from the copper, the solution will heat up, there will be red fumes, and the cement silver will float due to the gas formed as it redissolves.

To correct this I add a spoon or two of urea. There is much fizzing, but once it stops all the negative stuff goes away and the silver cements out nicely.

This experience would seem to indicate that the urea has neutralized at least some of the nitric acid.

I did read where urea and nitric acid form urea nitrate and if dried out can form an explosive, but not while it is wet or damp.

I still occasionally use urea in my gold and silver refining. It is a useful tool and I have not experienced anything bad from its use.

Have you had some bad experiences with it?

kadriver

Me the newbie in all this, just read something about the Urea, but am totally unsure,(lack of knowledge) and Butcher I'm sure will comment ....But I think I read that Urea changes the Ph in the solution...could be right ,could be wrong....haven't a clue, and was just trying to help

Scrap Happy,

Sorry man, did not want to confuse you.

I was just asking for clarity and sharing my experience with urea.

I used a video purchased off eBay several years ago when I first started trying to refine my own metal.

In that video they used urea to neutralize excess nitric acid before precipitating the gold out of a gold chloride solution (a solution of dissolved gold using aqua regia).

I am not trying to promote the use of urea in your refining. You can do refining and never have to use it.

Since I started off using it, urea is now in my chemical cabinet and I still use it very infrequently. There are times when it comes in handy so I keep some for those times.

Learning techniques such as adding nitric acid incrementally to form your aqua regia (this is a Goldsilverpro idea introduced to the forum) and using just enough nitric to dissolve silver is another.

Both of these techniques will completely eliminate the use of urea making it completely unnecessary.

Also, adding urea to the process does introduce a path for contamination to enter into your refining.

Please listen to butcher, as he has way more experience than I do.

I am only trying to share that my experience has been, the use of urea has had no noticeable adverse effects on my refining techniques.

Respectfully submitted, kadriver

Urea
I will try and explain the best I can as I understand it.

Nitric acid HNO3 can decompose, to HNO2, NO2, NO, and several other NOx gases, this decomposition can occur from many reactions, reactions with light, heat, metals, and other chemicals.

This gas or decomposed HNO3, can escape or still be in solution with HNO3, or our aqua regia.
the Urea will react to destroy the NO2 and other NOx gases dissolved in solution, like HNO2, but it will not destroy the HNO3.

when they make fuming nitric acid 98% HNO3 it normally will have decomposed NO2 gas in it coloring it red called red fuming nitric acid, when they want white fuming nitric acid, they need to get rid of the NO2 in the 98% HNO3, to do this on method is to add urea the Urea, destroys the NO2 gas in the nitric making urea nitrate, but it does not destroy the 98% HNO3, it removes NO2 giving a more pure nitric acid free of decomposed nitric called white fuming nitric acid.

Maybe you could decompose the nitric acid with adding a ton of urea to form urea nitrate, but it would add a lot of unwanted urea nitrate salts to your solution, I think where urea worked is if someone did not use too much excess of nitric when they used aqua regia, and only had a little NOx gas keeping gold from precipitating, they could add urea to remove the NO2 in solution and precipitate their gold, but if you added too much HNO3 and have free HNO3 in solution this method of adding urea does not work as well, without adding copious amounts of fertilizer to your solution.

the urea nitrate is an explosive, that can be dangerous, even if boiled in solution, normally I believe in solution it is less likely to explode when in solution, than when dried and heated strongly like in melting, but with what we do when we may have many different metals or chemical reactions going on in solution you never know, to me it is just not worth the risk, adding this to your solutions, what we deal with when we mix metals and acids can make explosive substances, refinery's have had explosions even from boiling aqua regia, I do not know the circumstances but I do not want to take the chance of it happening to me by adding something that can be avoided like urea nitrate to my solutions.

urea in nitrate or aqua regia with metals can also break down to ammonium compounds, these ammonium compounds, can also cause problems with PGM recovery or refining if you had these in solution, and as we Know ammonium compounds and some metals can also be dangerous.

Sulfamic acid in my opinion is cheap easy to get, works better than urea in my opinion and its byproducts can be beneficial to our aqua regia in the denoxing process (forming sulfuric acid in solution, which can help to keep from forming salts on evaporation, or help to remove lead as a sulfate), it can be bought at home depot, is safer to use.

I am late for work and do not really have time to finish my thought here, but maybe this will help for you to see why I say what I do with what I believe, like everyone else here I too am just learning.

Butcher, block your eyes! I too think hokes book is a bit old-fashioned. Not saying the lessons and knowledge is out-dated or anything, but you can tell it was written a while ago. LOL.

I love the gasoline on the fire bit. This was written with Darwin's principals in mind, the world would probably be a better place if everyone had to go outside and start a fire with gasoline.

Urea CO(NH2)2
or (NH2)2CO
or NH2CONH2

notice the carbonyl C=O group

equal mole of urea and concentrated nitric can make urea nitrate.
(NH2)2CO + HNO3 --> (NH2)2COHNO3
notice in the formula of urea nitrate we still have HNO3 in the formula.
This reaction as I stated earlier has the possibility of getting out of control which could cause ans explosive mixture.

urea nitrate can decompose by several different pathways
(NH2)2COHNO3 --> (NH3 + HNO3) + HNCO
notice ammonia, nitric (or ammonium nitrate) and isocyanic acid
(NH2)2COHNO3 -->NH3 + N2O + CO2 + H2O
notice nitrous oxide (laughing gas) and ammonia
(NH2)2COHNO3 <--> NH2CONH2 + HNO3
notice urea and nitric acid can form again on decomposition.

with nitrous acid
(NH2)2CO + 2 HNO3 --> CO2 + 2N2 + 3H2O

with nitrogen dioxide
2(NH2)2CO + 2NO2 -->2CO + 3N2 +4H2O

Also consider we not only have these gases and compounds in a solution of aqua regia, but we can have metals, and other substances reacting with these products or reactions, with that in mind there could be many many different reactions taking place, forming several other compounds in our solution or gases above our beaker,


=====================

Now lets look at sulfamic acid.
H3NSO3


its reaction with nitrous acid
HNO2 + H3NSO3 --> H2SO4 + N2 + H2O
and then nitric acid
HNO3 + H3NSO3 --> H2SO4 + N2O + H2O
notice the sulfuric acid forms here, as well as the nitrogen gases.

(formulas above were not checked for balance)


Best way to get rid of excess nitric acid in aqua regia is to not use excess HNO3 in the first place.
Adding gold to use up excess HNO3, or leaving some undissolved gold (heat and evaporating at this point is also very helpful).
Then the three evaporation process described in Hokes book.
Using sulfamic acid.
or a combination of one or all of the above.

urea I say is not needed, and can cause more harm than good.
My opinion your mileage may vary, and we all have a right to our own opinion here.

I'm a sulfamic acid believer, it's tried and true and works like a charm. I use it everyday.

Steve

What a Great Forum. As with HappyScrappy(?), I did the exact same thing with the GREEDY recycling plants, until I found a 5 gallon bucket of Hydrochloric acid left out by a stupid employee at some company that uses many other dangerous chemicals, and attempted to remove the gold myself. It's been several years of gathering any decent precious metal content electronics, computers, etc and breaking it all down and separating all the parts possible. I really need to learn this. I was looking for more toilet bowl cleaner with hydrochloric acid from the $1 store, when I came across a product with Sumfamic Acid.

Can I use this, instead of HCI to separate the gold from fingers and pins? Do I need to add something to dissolve the ferrous metals to possibly leave behind the silver, gold, platinum, nickel, etc for refining?

I will definitely download the book, especially since it sounds like easier reading than today's complicated chemical processes written by eccentric scientists stuck in a room for 10 years without ever seeing the daylight!!

Thomaseames,
I do not know of toilet bowl cleaners that use HCl acid.
I do not know what Sumfamic Acid is or what products would contain it.
So I cannot help you with this question.

Look for HCl at a place that sells concrete and brick, pool and spa chemical stores, your local hardware store...

Do not steal from a company even if they have stupid employees that leave chemicals out.
Look for grout cleaner with sulfamic acid.

Do not use any chemicals until you gain an understanding of the safety, a chemical may be fairly safe until something reacts with it like metals or other acids which then produce other dangers, you need to gain an understanding of the dangers throughout its use.

If you want to learn this complicated science you have found a good place.

Read dealing with waste and situations to avoid, and more in the safety section.

Read the general reaction list (the guide to the forum).

Welcome members.
Study the cupric chloride leaching process (wrongly named the acid peroxide process)...

Read Hoke's book.

This will help you get started.