rjamjb
Active member
- Joined
- Sep 6, 2015
- Messages
- 29
Hi,
It has been a while since I posted here I have a question relating to the picture which I've never come across as follows. Process first.
1. Collection of pins, gold plated parts primarily from old mobile phones and a few SIM cards over many months (there may have been an odd component in there although I tried to avoid including, being fairly meticulous about this).
2. Added HCL to cover (approx 0.5 litre) and then Nitric acid in small increments until all metals had dissolved.
3. Added Urea until any excess Nitric was gone.
4. Precipitated with SMB.
I got a normal drop from the SMB as I've done on a few occasions.
When I washed the powder in water it is clear that there are two powders, a light tan with about the amount of gold I'd expected (probably 1-1.5 grams) but also a 'dark powder'. When I swirl the powders they separate as you can see in the picture which is taken looking down into the beaker. One would appear to be more dense than the other.
I thought that I must have put too much SMB in and dropped another metal as well as gold, but this is not dissolving in conc HCL - the picture in the photo shows the two powders in HCL.
I've wondered whether i may have precipitated out a higher metal (Pd for example) but there would appear to be far too much compared with the gold.
Does anyone have an idea what the additional powder is? I've not seen this before. (the tan powder, Au, is not acclomorating in the usual way either, remaining very fine and silty, I suspect because of it being mixed with the other powder. At least with some idea what it is then that might give me the basis to separate it out.
Thanks.
KR
Russell
It has been a while since I posted here I have a question relating to the picture which I've never come across as follows. Process first.
1. Collection of pins, gold plated parts primarily from old mobile phones and a few SIM cards over many months (there may have been an odd component in there although I tried to avoid including, being fairly meticulous about this).
2. Added HCL to cover (approx 0.5 litre) and then Nitric acid in small increments until all metals had dissolved.
3. Added Urea until any excess Nitric was gone.
4. Precipitated with SMB.
I got a normal drop from the SMB as I've done on a few occasions.
When I washed the powder in water it is clear that there are two powders, a light tan with about the amount of gold I'd expected (probably 1-1.5 grams) but also a 'dark powder'. When I swirl the powders they separate as you can see in the picture which is taken looking down into the beaker. One would appear to be more dense than the other.
I thought that I must have put too much SMB in and dropped another metal as well as gold, but this is not dissolving in conc HCL - the picture in the photo shows the two powders in HCL.
I've wondered whether i may have precipitated out a higher metal (Pd for example) but there would appear to be far too much compared with the gold.
Does anyone have an idea what the additional powder is? I've not seen this before. (the tan powder, Au, is not acclomorating in the usual way either, remaining very fine and silty, I suspect because of it being mixed with the other powder. At least with some idea what it is then that might give me the basis to separate it out.
Thanks.
KR
Russell