A friend handed me a number of jugs with darkroom waste from platinum/palladium print developing. I am not sure what the chemistry is, so I am hoping someone knows the processes to recover.
I presume that there is something in there that stripped the pgms from prints during development. I don't know how that chemistry might get in the way.
I can test the chemistry with stannous chloride and don't really see a strong response but it is there. I infer that the concentration of PGMs is small.
I can test with dimethyl glyoxime and see a good bright yellow precipitate so I know at least that there IS some palladium in the chemistry.
I don't get much response with zinc to cement the PGMs. It seems unpredictable. I can get the amber liquid to go black, and on one experiment managed to get a little black powder at the bottom. I have been adding a little bit of HCl to deal with the zinc.
I had hoped to get the black powder. I am now trying to evaporate the amber chemistry down so that it is more concentrated, hoping that that will result in a stronger cementation.
My next step would have been to re-dissolve the PGMs into AR. Then Ammonium Chloride to get the platinum and then I thought I would go back to zinc just to get the palladium down by itself.
I am looking at this for no other reason than to learn the processes.
Anyone who has tried on darkroom Pt/Pd before who is willing to share some ideas?
I presume that there is something in there that stripped the pgms from prints during development. I don't know how that chemistry might get in the way.
I can test the chemistry with stannous chloride and don't really see a strong response but it is there. I infer that the concentration of PGMs is small.
I can test with dimethyl glyoxime and see a good bright yellow precipitate so I know at least that there IS some palladium in the chemistry.
I don't get much response with zinc to cement the PGMs. It seems unpredictable. I can get the amber liquid to go black, and on one experiment managed to get a little black powder at the bottom. I have been adding a little bit of HCl to deal with the zinc.
I had hoped to get the black powder. I am now trying to evaporate the amber chemistry down so that it is more concentrated, hoping that that will result in a stronger cementation.
My next step would have been to re-dissolve the PGMs into AR. Then Ammonium Chloride to get the platinum and then I thought I would go back to zinc just to get the palladium down by itself.
I am looking at this for no other reason than to learn the processes.
Anyone who has tried on darkroom Pt/Pd before who is willing to share some ideas?
