Wingedcloud
Well-known member
- Joined
- Nov 6, 2014
- Messages
- 96
Hello everynone. I am new to this forum, but for the little time I've been here, I know I've come to the right place to get some support in my "quest" to recover some precious metals from PCB's, which leaves me happy, because I was feeling a little unsupported trying to do something right.
If I may, I'm gonna start by telling a little bit about my background.
I recently finished my Master's Degree in Environmental Engineering and i did my master's thesis in recovering precious metals from PCB's by hydrometallurgical methods.
During my work, i tested dissolving the metals in aqua regia and precipitating the gold by means of ferrous sulphate and sodium nitrite. During my research, I've come across Hoke's book, and knew about some of the existing processes there are to recover gold from solution. However, having an academic background, I'm used to having some concrete values and experimental conditions, some characteristics this book lacks in some extent. Im not saying that that information not only but also emphyrical, result of much years of working in this "business", are inferior to some information I found in some scientific papers and articles during my thesis research, and I am more than ready to follow those instructions if that means I'm going to suceed.
After I finished my thesis, I kept reading, studying and searching for more information about hydrometallurgy and even got some powder out of some CPU's I expect to be gold. Just waiting to have material to melt it and find out
I have a lot of material waiting to be processed, like some more CPU's, memory sticks, motherboards, cellphone boards, etc.
But enough of my story...on to my questions:
Regarding an initial HNO3 base metals removal:
- Which mass/volume ratio should I use?
- At which temperature should this process be done and for how long?
Regarding AR precious metals removal:
- Should I follow Hoke's 1:3/1:4 HNO3/HCl ratio or do the "small HNO3 aditions" process? When do I know I've added enough HNO3?
- At which temperature should this process be done and for how long? (during my thesis I used 90ºC for 3 hours)
Regarding gold recovery from solution:
- SMB vs Ferrous Sulphate vs Sulfur Dioxide ?
I've found this video about sulfur dioxide gold recovery and I would like to know your opinion about using it on PCB's aqua regia gold removal, considering the gold content is much lower than the one on the video.
https://www.youtube.com/watch?v=1Usv2Lh10nQ
- Should I heat my solution to do this process?
I would like to say thanks in advance to someone who can help me with my questions and apologize if there are answers somewhere in this forum and I've not been able to find them. Feel free to ask anything that can help you help me
Best regards to you all
If I may, I'm gonna start by telling a little bit about my background.
I recently finished my Master's Degree in Environmental Engineering and i did my master's thesis in recovering precious metals from PCB's by hydrometallurgical methods.
During my work, i tested dissolving the metals in aqua regia and precipitating the gold by means of ferrous sulphate and sodium nitrite. During my research, I've come across Hoke's book, and knew about some of the existing processes there are to recover gold from solution. However, having an academic background, I'm used to having some concrete values and experimental conditions, some characteristics this book lacks in some extent. Im not saying that that information not only but also emphyrical, result of much years of working in this "business", are inferior to some information I found in some scientific papers and articles during my thesis research, and I am more than ready to follow those instructions if that means I'm going to suceed.
After I finished my thesis, I kept reading, studying and searching for more information about hydrometallurgy and even got some powder out of some CPU's I expect to be gold. Just waiting to have material to melt it and find out
I have a lot of material waiting to be processed, like some more CPU's, memory sticks, motherboards, cellphone boards, etc.
But enough of my story...on to my questions:
Regarding an initial HNO3 base metals removal:
- Which mass/volume ratio should I use?
- At which temperature should this process be done and for how long?
Regarding AR precious metals removal:
- Should I follow Hoke's 1:3/1:4 HNO3/HCl ratio or do the "small HNO3 aditions" process? When do I know I've added enough HNO3?
- At which temperature should this process be done and for how long? (during my thesis I used 90ºC for 3 hours)
Regarding gold recovery from solution:
- SMB vs Ferrous Sulphate vs Sulfur Dioxide ?
I've found this video about sulfur dioxide gold recovery and I would like to know your opinion about using it on PCB's aqua regia gold removal, considering the gold content is much lower than the one on the video.
https://www.youtube.com/watch?v=1Usv2Lh10nQ
- Should I heat my solution to do this process?
I would like to say thanks in advance to someone who can help me with my questions and apologize if there are answers somewhere in this forum and I've not been able to find them. Feel free to ask anything that can help you help me
Best regards to you all