Some little problems on Memory Ram Yields

[skullsbox01]

Hi People,
i have processed 2kg of ram memories, i have cut the fingers and i have obtained 175 grams.
The fingers have been processed for first step in solution with 50% HNO3 and 50% H2O.
After this process i have filtered the gold, and i have processed it in AR.
After dissolution, i have used SMB to drop down the gold.
The yield of this process for 2Kg of memory Ram have been only 0,37 grams.
I have read on this forum that the yield of memory Ram is around 0,5 grams for kilo, but in my case the yield is 0,18grams for kilo.

Where is my error?

(in the pictures there are the materials that i have worked and the gold that i have obtained).

Thanks

 

[FrugalRefiner]

Two thoughts come to mind.

First, the fingers are not what most would consider closely cut. There is a lot of extra green circuit board in those 175 grams of fingers. So your recovery from the fingers is probably about right.

Second, have you processed the chips from the RAM? Many of those memory chips will have gold bonding wires embedded in the package. There are several ways of processing them, all of which are discussed here on the forum.

Dave

 

[solar_plasma]

Have you used far more than 2-3 ml nitric for your AR?

 

[skullsbox01]

Hi Dave, the weight that i consider for the yield is the total weight of the memories Ram, so the yield of 0,5 grams for Kilo is calculated on the total weight. The gold in the black cip, is around 3% of the total yield, than is not considerable for this test.

Hi Solar, i have used much nitric acid, because gold was in the filter and than i have processed also the filter, but after the dissolution process i have used the Urea to neutralizing nitric acid.

Thanks to all. 8)

 

[niteliteone]

I don't know how to explain to someone that their is MORE gold in those chips than on the fingers processed as was already mentioned and "Ignored" :shock:
or worse. reduced to pettiness :roll:
But I guess the OP knows more than the people he is asking for help :lol:

 

[solar_plasma]

Nevertheless there should be 0,5g/kg gold in the plating. I guess you have lost some gold in the process, could be caused by the filter technique or still in solution.

Urea isn't recommended in this forum anymore. Most would use CuCl2 leach instead of nitric in the first step. I guess no one would use AR for the second step, but HCl/chlorox. Ofcourse your method works, but it is full of snares and more difficult than it must be, which easily results in suboptimal yields.


...btw why should gold foils stay in the filters? All in all that whole thing doesn't sound as if you have good skills and proper methods, learn from the forum and review your methods, is my advice.

 

[niteliteone]

If the H2O used was Not distilled or RODI it more than likely contained something that took some gold into solution in the first base metal removal step. Not sure if it can happen with nitric, but something to think of.

I have watched HCl and "my" water dissolve gold and I live in the country with my own water well. Then again my water also dissolves brass and copper water fittings. Slowly over a few years they just split and spray water.

 

[skullsbox01]

Niteliteone, i don't belives that the gold is more in the IC Chips than fingers, because the ram yield is around 600/700 grams for tonns, and the fingers yield, removed from one tonn of ram memories, is around 500/600 grams. The water that i have used is distilled water.

Solar, i have used nitric acid in the first step because it is very fast, in two hours i have removed all gold from the fingers. After filtering, the gold was all in the filter and i have processed it for avoiding losses.

Thanks to all

 

[solar_plasma]

TSOP44...54: 0,1% gold
SOJ44: 0,046% gold
(Source: Testing black chips and SMD packages on their raw gold content by R. Eugster)

In practice you will find about 0,5/kg of ram only in the chips. I understand it is all new to you. If refining would be like your city, you haven't even gone outside your house. At this point everything you think is a news, is an old hat, discussed and proved in depth in this forum. Read the forum for some weeks and we can talk. Those yields do match to my own practice and to all experiences of other's I read on the forum, so this test can be taken as validated.

It is a bit harder to those who already know a little, than to those, who come here as a blank paper. Just like me in the beginning, you will first have to realize, how much you don't know and how much knowledge you will find here. Welcome to this ingenious forum!

 

[niteliteone]

Well you clearly didn't get what you were supposed to have. Your numbers, not mine :roll:
We have covered practically every place you could have loss with out realizing it.
So what else is wrong or what have you not told :?:
Did you blow some of the gold powder away when you melted it :?:

Something to think about with the numbers you are using;
I went back and looked at your picture above and noticed your ram showing is single sided and looks newer than most of what I have ran, (Mostly EDO) which did contain more gold in the chips than the fingers.
So if what you are processing is not the same as the numbers you are using, that can also account for the low recovery

 

[solar_plasma]

Did you incinerate the filters properly to white ash before you processed them?

 

[skullsbox01]

Solar, i have read the forum and the average yield that i think of ram fingers is compatible with the average that i have read on the forum.

This is a link http://goldrefiningforum.com/~goldrefi/phpBB3/viewtopic.php?f=41&t=4919 , there is your post where you say that, you have received 0,2g of foils from 12 pieces of ram.

The average weight of the ram memories is around 18 grams, so 12 pieces x 18 grams = 216 grams, and 0,2 grams are 0,09%, .

Thanks to all

 

[solar_plasma]

you have received 0,2g of foils from 12 pieces of ram.

yap, but I have to add, foils are not refined gold, there may be impurities of small bits of green solder mask and the foils themselves do not need to be 24 karat. Further it was weighed on a O,1g-weight, so it will not be 0,2000g but +/-0,05g. The RAM I used was only DDR2 of good quality, so it also might be an artifact.

Normally I get about 0,5g/kg from mixed ram (only the plating), so it should not wonder, that some ram's yield 1g of foils (inculding impurities) from 1kg ram boards.

according to my other statements: I think in a year you will know, what I mean. I at least can just shake my had about my own ignorance one year ago

 

[nickvc]

The one thing to remember is that processing small amounts rarely gets a good return compared to doing big quantities when done correctly. Small amounts left on the filter paper, spills, foils stuck to beakers etc... In large volumes a loss of 0.1 grams is negligible with 0.2 - 0.5 it's massive percentage wise.

 

[solar_plasma]

The one thing to remember is that processing small amounts rarely gets a good return compared to doing big quantities when done correctly. Small amounts left on the filter paper, spills, foils stuck to beakers etc... In large volumes a loss of 0.1 grams is negligible with 0.2 - 0.5 it's massive percentage wise.

exactly! This is what I meant with filter technique and proper incineration, just by those you could have a loss of 0,1g or more, which would make a significant difference.

 

[skullsbox01]

Thanks to all, the important thing is that the average yield for ram is around 0,5 g/kg if we consider only the plated finger.
I will try another process to refine the gold finger. I will tell you the yield of the new process.
Obviously, i will consider that a small loss in a small batch is a considerable percentage.


Thanks for the moment 8)

 

[nickvc]

Please note while I said loss in reality if you have removed all the gold from the fingers and you haven't thrown anything away it is recoverable at a later date, good house keeping in refining is important to minimise losses.

 

[skullsbox01]

thanks for the tips... the gold will be somewhere but where?
I proceed for a new process, i'm sure that will be well.

:lol:

 

[solar_plasma]

Before you start your next batch, you can post detailed what you are going to do, then we can give you useful hints or corrections or confirm, that you have understood every important little detail right.

 

[skullsbox01]

i have just started a new process on 180g of ram fingers coming from 2kg of ram, in HCl and some small addition of HNO3 at the temperature of 75°.

In this mode i avoid more steps, the gold is dissolved in the first step. After dissolution, the solution will filtered and after the gold will be drop downed with SMB. The estimated yield is 1gram, then i use 0,7 grams of SMB

I know that this mode can't be the best mode, but i try it now, and after, if the yield is not the best, i will try another method.