Need to remove salts out of a messed up mix

[narori]

Hello,
I started a recovery process from different computer parts, few cell phone parts and even jewelry (about a lb of mixed material). I was not well prepared and wanted to gain some experience. I put all together in HCl and heated it up until it started evaporating. Then I started adding HNO3 (15 M), and I am sure that it was too much. After the solution was not reacting with the nitric (and after too much of it). I cooled it in a vase with ice cubes. I let it settle and found lots of gold foil in the sand. I added SMB and also added too much. I was afraid of loosing my gold, so I mixed all back together.
Now I have two batches: One that has sands made of salts of different metals, SMB, and some gold foils. I am using AP to try to separate the sands (salts) from the gold foils.
The second batch is a solution of AR that I am evaporating, and adding fresh HCl, as Hocke recommends.
I did not know about this forum when I started. Now I have spent some time reading the forum threads and read Hocke a couple of times. Still I would appreciate some input from some of the experience gurus/ patriarchs of the gold refining world. thanks in advance and just go ahead and chew my ear. I deserve it, and please give me some advice.

 

[ericrm]

well... you did it! you gain some experience 8)

 

[nickvc]

Well I think mess is a fair description but fear not it can be corrected and you will certainly gain experience trying to put it right. The first things to do is stop all chemical additions and take your solution off heat, filter both solutions and cement any values, having tested for them using stannous chloride, with a large piece of copper placed in the solution. The filtered solids and sand will contain most of the values but also a mix of unwanted metals this will need to be crushed and incinerated, brought to a red heat slowly and kept there for several minutes and with stirring to ensure all the material is incinerated, allow to cool place in a beaker and add hydrochloric slowly and bring up to a high heat again stirring the solids this should remove many unwanted materials such as tin but you may need to do this several times, test the solution with stannous it's good practice before safely disposing of the spent solution. Then you need to filter and wash well with water again check the solution with stannous and then incinerate again. Put the material back into your beaker and half fill with water on heat and slowly add nitric only adding more as all reaction stops this should remove the vast majority of the remaining base metals and any silver or palladium in the mix, once all reaction has stopped cool and filter and rinse with water several times, this solution will contain any silver or palladium which is recovered by cementation with copper. What you now have left should be any gold and possibly some PGMs and a little base metals, these can be added to the powder if any cemented out of your original solutions which can now be dissolved with either AR or the chlorox method and as this is such a mix a little sulphuric would be advisable to remove any lead once the solution is cold and filtered.
I think this should work but if not I'm sure better suggestions will be added and now you really will get some experience, I bet you won't do this again.
Welcome to the forum and good luck.

 

[butcher]

While following Nickvc's advice, also keep studying Hoke's book, her book will help fill in the small details of the process, and give you a better understanding of recovey and refining.

 

[narori]

thanks for the advise. I will follow your directions.

 

[narori]

Hi again,
I could finally return to my work.
I filtered both solutions and working on them separately.
Both gave positive with stannous chloride.
I added a large piece of copper and ne of the filtered solutions but after two days, I returned and my copped was almost gone, and the solution turned very dark. I am filtering that solution right now but it does go to the larger filter (coffee filter)too easily, like if they were no major solids.
I thought of letting it sit for a few hours and then use a better filter.
Also the reacdtion with the copper means that all of the metals that are higher in reactivity have already gotten out of solution?
thanks in advance