Geo
Well-known member
I had enough free time to work on some secondary stuff I have been collecting. I process whole boards, such as ram, video and sound cards, some CPU's, and a few other high end boards in AP to both liberate the foils as well as chips and SMD's. Through a screening process, the chips are removed and anything larger than the smaller tantalum capacitors. Anything smaller goes on to the next process where I dissolve the gold foils from the remaining solids with HCl and bleach. I enjoy pretty good success doing this and it leaves the MLCC's and film resistors virtually intact. The leech is not on the material long enough to dissolve any PGM's and any that it does comes out in the stock pot.
So I rediscovered a container of mixed SMD's that has gone through this process and decided to give Pd another try. Only this time, I wasn't going to try and refine. I was going to make as pure a solution as I could and cement the Pd out using aluminium turnings. I then cleaned the cemented powder with a boiling, dilute HCl bath. I followed this with a boiling Dilute sulfuric acid bath. I followed this with several boiling water rinses. All of this on a hot plate stirrer with good stirring. I dried the powder and roasted it over a camp stove flame. I then melted it using propane/oxy cutting tip in a high back melting dish. I will have it assayed Monday. I think it was a decent result.
So I rediscovered a container of mixed SMD's that has gone through this process and decided to give Pd another try. Only this time, I wasn't going to try and refine. I was going to make as pure a solution as I could and cement the Pd out using aluminium turnings. I then cleaned the cemented powder with a boiling, dilute HCl bath. I followed this with a boiling Dilute sulfuric acid bath. I followed this with several boiling water rinses. All of this on a hot plate stirrer with good stirring. I dried the powder and roasted it over a camp stove flame. I then melted it using propane/oxy cutting tip in a high back melting dish. I will have it assayed Monday. I think it was a decent result.